There is a bug in the current version of the framework whereby if no ApplicationContext is supplied then you will get a generic rules engine execution error like the below. Can you try setting an ApplicationContext against the pipeline and see if that
resolves your issue? I have fixed this in v1.5 which is still work in progress, ApplicationContext will be truly optional now.
If that doesn't work then the best course of action would be to download the latest source code (or I could send you an installer) for v1.5 of the framework which is a few weeks away from being released (I am still ironing out a few bugs and implementing
a few more features).
In v1.5 you no longer get generic exception messages if an exception was encountered in the rules engine, you instead get the outer and inner most exception messages which should give us a clue as to why you are having this problem.
Let me know what works for you. I am keen to get to the bottom of this error and fix it in v1.5 if it isn't already fixed.