I just found the cause that let MIDI Rules hang up.
Currently if you use MIDI Rules for a while and specially if you trigger the controls fast, MIDI Rules will stop working.
The cause is a deadlock the timer code of MIDI Rules. (If you press ctrl+break in the MIDI Rules console window you can see the heap dump of the Java VM).
I will publish a bug fix release of MIDI Rules Prototype in the next days. So keep an eye on this blog.
P.S.: Sorry Behringer that I thought it’s a bug in the BCD2000 Hardware 😉