I've made an article how to build but it seems to change rapidly:D
Here is an update but I'm not 100% Is it works:D
1) install git
2) git clone https://github.com/bpmc/bpm-console.git
3) mvn clean install -U -Dconsole.profile=jbpm -Dfull -DskipTests
5) git clone https://github.com/droolsjbpm/jbpm.git
6) mvn clean install -U -Dfull -DskipTests
7) git clone https://github.com/droolsjbpm/jbpm-form-builder
8) mvn clean install -U -Dfull -DskipTests
9) take installer You just built and extract it somewhere, $installer-dir$
10) put form builder and console wars to lib dir in $installer-dir$
15) in $installer-dir$ run:
ant clean.demo
ant install.demo (or ant install.demo.noeclipse if you dont want eclipse)
ant start.demo (or ant start.demo.noeclipse if you dont want eclipse)
tell me if it worked:D If Your connection isnt very good its better to use *.noeclipse version