Is there any other tool which is more user friendly in regard to BPR including the one K2 bpm suite you recommend?

I haven't used K2bpm suite per se to be able to make a suitable comment about it, but try one from http://www.businessgenetics.com/ as per your need.
I have found their products very user-friendly and comprehensive.

Actually people have sometimes their application developed in different technologies so process re-engineering requires to act accordingly so that is why organization always select the bpr tool as per their application otherwise your redesigned process will be nothing but a process without interface.