It didn't work, and ilasm's error output is, well, it stinks. It doesn't tell you anything at all about why it didn't work.
Does anyone still have a copy of the setup file for C# 2005?
I'm installing SharpDevelop now. The latest version supports .Net 2.0, 3.0 and 3.5.
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For my purposes at least, SharpDevelop isn't working either. I'm currently working on pairing down the functions I've created to figure out which one it's having issues with. Everything looks fine until I go to build it in DLL_Tool, and it gives an error, but there's no real meaning behind the error. Very frustrating..