I've done the step 1~4 according your guide, and everything seems fine.

And still when issuing the "picketlink-setup --feature idm", I got the same error message of "**ERROR** Could not load type."

Here's the message from command line:
[Customer.java]$ picketlink-setup
Downloading: http://repo1.maven.org/maven2/org/picketlink/picketlink-api/maven-m
etadata.xml
Downloaded: http://repo1.maven.org/maven2/org/picketlink/picketlink-api/maven-me
tadata.xml (2 KB at 4.2 KB/sec)
**SUCCESS** PicketLink [2.7.0.Beta1] has been installed.
[picketlink-forge-app]$ picketlink-setup --feature idm
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building picketlink-forge-app 1.0.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] — maven-clean-plugin:2.5:clean (default-clean) @ picketlink-forge-app -
–
[INFO] Deleting D:\blade-workspace\picketlink-forge-app\target
[INFO]
[INFO] — maven-resources-plugin:2.6:resources (default-resources) @ picketlink
-forge-app —
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO]
[INFO] — maven-compiler-plugin:3.1:compile (default-compile) @ picketlink-forg
e-app —
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 3 source files to D:\blade-workspace\picketlink-forge-app\targe
t\classes
[INFO]
[INFO] — maven-resources-plugin:2.6:testResources (default-testResources) @ pi
cketlink-forge-app —
[INFO] Not copying test resources
[INFO]
[INFO] — maven-compiler-plugin:3.1:testCompile (default-testCompile) @ picketl
ink-forge-app —
[INFO] Not compiling test sources
[INFO]
[INFO] — maven-surefire-plugin:2.12.4:test (default-test) @ picketlink-forge-a
pp —
[INFO] Tests are skipped.
[INFO]
[INFO] — maven-war-plugin:2.4:war (default-war) @ picketlink-forge-app —
[INFO] Packaging webapp
[INFO] Assembling webapp [picketlink-forge-app] in [D:\blade-workspace\picketlin
k-forge-app\target\picketlink-forge-app]
[INFO] Processing war project
[INFO] Copying webapp resources [D:\blade-workspace\picketlink-forge-app\src\mai
n\webapp]
[INFO] Webapp assembled in [62 msecs]
[INFO] Building war: D:\blade-workspace\picketlink-forge-app\target\picketlink-f
orge-app.war
[INFO]
[INFO] — maven-install-plugin:2.4:install (default-install) @ picketlink-forge
-app —
[INFO] Installing D:\blade-workspace\picketlink-forge-app\target\picketlink-forg
e-app.war to C:\Users\tonny\.m2\repository\org\picketlink\forge\app\picketlink-f
orge-app\1.0.0-SNAPSHOT\picketlink-forge-app-1.0.0-SNAPSHOT.war
[INFO] Installing D:\blade-workspace\picketlink-forge-app\pom.xml to C:\Users\to
nny\.m2\repository\org\picketlink\forge\app\picketlink-forge-app\1.0.0-SNAPSHOT\
picketlink-forge-app-1.0.0-SNAPSHOT.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.970 s
[INFO] Finished at: 2014-08-31T15:14:04+08:00
[INFO] Final Memory: 67M/1224M
[INFO] ------------------------------------------------------------------------
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building picketlink-forge-app 1.0.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] — maven-clean-plugin:2.5:clean (default-clean) @ picketlink-forge-app -
–
[INFO] Deleting D:\blade-workspace\picketlink-forge-app\target
[INFO]
[INFO] — maven-resources-plugin:2.6:resources (default-resources) @ picketlink
-forge-app —
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO]
[INFO] — maven-compiler-plugin:3.1:compile (default-compile) @ picketlink-forg
e-app —
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 4 source files to D:\blade-workspace\picketlink-forge-app\targe
t\classes
[INFO]
[INFO] — maven-resources-plugin:2.6:testResources (default-testResources) @ pi
cketlink-forge-app —
[INFO] Not copying test resources
[INFO]
[INFO] — maven-compiler-plugin:3.1:testCompile (default-testCompile) @ picketl
ink-forge-app —
[INFO] Not compiling test sources
[INFO]
[INFO] — maven-surefire-plugin:2.12.4:test (default-test) @ picketlink-forge-a
pp —
[INFO] Tests are skipped.
[INFO]
[INFO] — maven-war-plugin:2.4:war (default-war) @ picketlink-forge-app —
[INFO] Packaging webapp
[INFO] Assembling webapp [picketlink-forge-app] in [D:\blade-workspace\picketlin
k-forge-app\target\picketlink-forge-app]
[INFO] Processing war project
[INFO] Copying webapp resources [D:\blade-workspace\picketlink-forge-app\src\mai
n\webapp]
[INFO] Webapp assembled in [57 msecs]
[INFO] Building war: D:\blade-workspace\picketlink-forge-app\target\picketlink-f
orge-app.war
[INFO]
[INFO] — maven-install-plugin:2.4:install (default-install) @ picketlink-forge
-app —
[INFO] Installing D:\blade-workspace\picketlink-forge-app\target\picketlink-forg
e-app.war to C:\Users\tonny\.m2\repository\org\picketlink\forge\app\picketlink-f
orge-app\1.0.0-SNAPSHOT\picketlink-forge-app-1.0.0-SNAPSHOT.war
[INFO] Installing D:\blade-workspace\picketlink-forge-app\pom.xml to C:\Users\to
nny\.m2\repository\org\picketlink\forge\app\picketlink-forge-app\1.0.0-SNAPSHOT\
picketlink-forge-app-1.0.0-SNAPSHOT.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.228 s
[INFO] Finished at: 2014-08-31T15:14:06+08:00
[INFO] Final Memory: 65M/1223M
[INFO] ------------------------------------------------------------------------
**ERROR** Could not load type.

And, here's the error in forge.log
15:14:06,941 SEVERE [org.jboss.forge.addon.shell.aesh.CommandAdapter] (AeshProcess: 8) Failed to execute [picketlink-setup] due to exception.: java.lang.RuntimeException: Could not load type.
at org.picketlink.tools.forge.operations.PersistenceOperations.configure(PersistenceOperations.java:122)
at org.picketlink.tools.forge.operations.ConfigurationOperationsImpl.newIdentityManagementConfiguration(ConfigurationOperationsImpl.java:70)
at org.picketlink.tools.forge.ui.idm.JPAIdentityStoreSetupWizardStep.execute(JPAIdentityStoreSetupWizardStep.java:65)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_51]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_51]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_51]
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_51]
at org.jboss.forge.furnace.proxy.ClassLoaderInterceptor$1.call(ClassLoaderInterceptor.java:87) [furnace-proxy-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.furnace.util.ClassLoaders.executeIn(ClassLoaders.java:40) [furnace-api-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.furnace.proxy.ClassLoaderInterceptor.invoke(ClassLoaderInterceptor.java:103) [furnace-proxy-2.8.1.Final.jar:2.8.1.Final]
at org.picketlink.tools.forge.ui.idm.JPAIdentityStoreSetupWizardStep_$$javassist_1df2d614-81db-46b8-b048-f716540769f8.execute(JPAIdentityStoreSetupWizardStep$$_javassist_1df2d614-81db-46b8-b048-f716540769f8.java)
at org.jboss.forge.addon.ui.impl.controller.WizardCommandControllerImpl.execute(WizardCommandControllerImpl.java:153) [ui-impl-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.addon.ui.impl.controller.NoUIWizardControllerDecorator.execute(NoUIWizardControllerDecorator.java:152) [ui-impl-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.addon.shell.aesh.CommandAdapter.execute(CommandAdapter.java:74) [shell-impl-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.aesh.console.AeshConsoleImpl$AeshConsoleCallbackImpl.execute(AeshConsoleImpl.java:325) [aesh-0.56.jar:0.56]
at org.jboss.aesh.console.AeshProcess.run(AeshProcess.java:40) [aesh-0.56.jar:0.56]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_51]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_51]
at java.lang.Thread.run(Thread.java:744) [rt.jar:1.7.0_51]
Caused by: java.lang.RuntimeException: Could not load type [/org/picketlink/forge/app/view/ViewUtils].
at org.picketlink.tools.forge.operations.PersistenceOperations$1.visitFile(PersistenceOperations.java:180)
at org.picketlink.tools.forge.operations.PersistenceOperations$1.visitFile(PersistenceOperations.java:153)
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:135) [rt.jar:1.7.0_51]
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:199) [rt.jar:1.7.0_51]
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:199) [rt.jar:1.7.0_51]
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:69) [rt.jar:1.7.0_51]
at java.nio.file.Files.walkFileTree(Files.java:2600) [rt.jar:1.7.0_51]
at java.nio.file.Files.walkFileTree(Files.java:2633) [rt.jar:1.7.0_51]
at org.picketlink.tools.forge.operations.PersistenceOperations.findEntityTypes(PersistenceOperations.java:153)
at org.picketlink.tools.forge.operations.PersistenceOperations.configure(PersistenceOperations.java:89)
... 18 more
Caused by: java.lang.ClassNotFoundException: /org/picketlink/forge/app/view/ViewUtils
at java.net.URLClassLoader$1.run(URLClassLoader.java:366) [rt.jar:1.7.0_51]
at java.net.URLClassLoader$1.run(URLClassLoader.java:355) [rt.jar:1.7.0_51]
at java.security.AccessController.doPrivileged(Native Method) [rt.jar:1.7.0_51]
at java.net.URLClassLoader.findClass(URLClassLoader.java:354) [rt.jar:1.7.0_51]
at java.lang.ClassLoader.loadClass(ClassLoader.java:425) [rt.jar:1.7.0_51]
at java.lang.ClassLoader.loadClass(ClassLoader.java:358) [rt.jar:1.7.0_51]
at org.picketlink.tools.forge.operations.PersistenceOperations$1.visitFile(PersistenceOperations.java:178)
... 27 more

15:14:06,945 SEVERE [org.jboss.forge.addon.shell.aesh.CommandAdapter] (AeshProcess: 8) Could not load type.: java.lang.RuntimeException: Could not load type.
at org.picketlink.tools.forge.operations.PersistenceOperations.configure(PersistenceOperations.java:122)
at org.picketlink.tools.forge.operations.ConfigurationOperationsImpl.newIdentityManagementConfiguration(ConfigurationOperationsImpl.java:70)
at org.picketlink.tools.forge.ui.idm.JPAIdentityStoreSetupWizardStep.execute(JPAIdentityStoreSetupWizardStep.java:65)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_51]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_51]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_51]
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_51]
at org.jboss.forge.furnace.proxy.ClassLoaderInterceptor$1.call(ClassLoaderInterceptor.java:87) [furnace-proxy-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.furnace.util.ClassLoaders.executeIn(ClassLoaders.java:40) [furnace-api-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.furnace.proxy.ClassLoaderInterceptor.invoke(ClassLoaderInterceptor.java:103) [furnace-proxy-2.8.1.Final.jar:2.8.1.Final]
at org.picketlink.tools.forge.ui.idm.JPAIdentityStoreSetupWizardStep_$$javassist_1df2d614-81db-46b8-b048-f716540769f8.execute(JPAIdentityStoreSetupWizardStep$$_javassist_1df2d614-81db-46b8-b048-f716540769f8.java)
at org.jboss.forge.addon.ui.impl.controller.WizardCommandControllerImpl.execute(WizardCommandControllerImpl.java:153) [ui-impl-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.addon.ui.impl.controller.NoUIWizardControllerDecorator.execute(NoUIWizardControllerDecorator.java:152) [ui-impl-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.forge.addon.shell.aesh.CommandAdapter.execute(CommandAdapter.java:74) [shell-impl-2.8.1.Final.jar:2.8.1.Final]
at org.jboss.aesh.console.AeshConsoleImpl$AeshConsoleCallbackImpl.execute(AeshConsoleImpl.java:325) [aesh-0.56.jar:0.56]
at org.jboss.aesh.console.AeshProcess.run(AeshProcess.java:40) [aesh-0.56.jar:0.56]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_51]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_51]
at java.lang.Thread.run(Thread.java:744) [rt.jar:1.7.0_51]
Caused by: java.lang.RuntimeException: Could not load type [/org/picketlink/forge/app/view/ViewUtils].
at org.picketlink.tools.forge.operations.PersistenceOperations$1.visitFile(PersistenceOperations.java:180)
at org.picketlink.tools.forge.operations.PersistenceOperations$1.visitFile(PersistenceOperations.java:153)
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:135) [rt.jar:1.7.0_51]
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:199) [rt.jar:1.7.0_51]
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:199) [rt.jar:1.7.0_51]
at java.nio.file.FileTreeWalker.walk(FileTreeWalker.java:69) [rt.jar:1.7.0_51]
at java.nio.file.Files.walkFileTree(Files.java:2600) [rt.jar:1.7.0_51]
at java.nio.file.Files.walkFileTree(Files.java:2633) [rt.jar:1.7.0_51]
at org.picketlink.tools.forge.operations.PersistenceOperations.findEntityTypes(PersistenceOperations.java:153)
at org.picketlink.tools.forge.operations.PersistenceOperations.configure(PersistenceOperations.java:89)
... 18 more
Caused by: java.lang.ClassNotFoundException: /org/picketlink/forge/app/view/ViewUtils
at java.net.URLClassLoader$1.run(URLClassLoader.java:366) [rt.jar:1.7.0_51]
at java.net.URLClassLoader$1.run(URLClassLoader.java:355) [rt.jar:1.7.0_51]
at java.security.AccessController.doPrivileged(Native Method) [rt.jar:1.7.0_51]
at java.net.URLClassLoader.findClass(URLClassLoader.java:354) [rt.jar:1.7.0_51]
at java.lang.ClassLoader.loadClass(ClassLoader.java:425) [rt.jar:1.7.0_51]
at java.lang.ClassLoader.loadClass(ClassLoader.java:358) [rt.jar:1.7.0_51]
at org.picketlink.tools.forge.operations.PersistenceOperations$1.visitFile(PersistenceOperations.java:178)
... 27 more