Download:
https://repository.jboss.org/nexus/service/local/repositories/releases/content/org/jboss/windup/windup-distribution/2.0.0.Beta8/windup-distribution-2.0.0.Beta8-offline.zip

Issues resolved in this release:

Bug WINDUP-455 Can't compile against Java 8
Bug WINDUP-452 NPE when executing windup from addon within Forge plugin in JBDS
Bug WINDUP-451 Seeing NullPointerException when executing windup