It's been over a year since the time I left the Activelock project, due to lack of time, after having coded the baseline for 2.0. I just checked in to have a quick peek a few days ago, and it looks like it's made great strides since. Kudos to Ismail for doing a great job keeping the project alive.
Back then I had to deal with low-level RSA and MD5 bit mangling in pure C/C++. Granted that much of the encryption code was "borrowed" heavily from the PuTTY project, but, boy, was debugging it ever a nightmare.
If I were to do it all over again now, I'd rewrite the core in .NET--It's sooo much easier now with all the encryption facilities built into the core .NET framework.
I've noticed that every time I do any code weaving in .NET, it seems to take 10 times faster to get things done than doing it the old ways. Suddenly, you're presented with many new possibilities.