I'll try to answer your question(s) to the best of my ability:
>>Since they have meen bought out by cisco....
I cannot say if Cisco bought Psionic; I know they took over psionic.com but that's the extent of my knowledge.
>>does this mean the software is no longer usable ...
I understood the Trisentry suite was distributed under the GNU license. By reading the license agreement I don't see anything that would indicate that you have to stop using it (or developing) in the event of ownership transfer - Best ask Cisco this question.
In so far as your other two questions; again these are license related and would best be answered by Cisco.
Hope that helps...
Glenn Graham (Author)