Encog 2.0 Dot Net has been released to beta test status
Encog 2.0 adds many new features to the Encog API. Some of these include recurrent neural networks, RPROP training, advanced pruning, and many other features.
Encog 2.0 DotNet has been released as beta-1. I think its pretty solid, but, of course, let me know if you run into any issues. The download is here:
http://code.google.com/p/encog-cs/downloads/list
If you want the 2.0 workbench, just use the Java one. Its packaged as a windows executable, and reads/writes/generates all the same files that the C# version needs. Encog data files are the same between C# and Java.