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If the question were, instead...
"How do I make this completely Microsoft-dependent software system work on Linux?"
...my response would have been basically the same, but in reverse - Use Perl. Sure, there's Mono (which does work fairly well) but for something like this - a piece of software with a GUI that must run on users' desktops - you are asking for trouble if you do anything outside of Microsoft's preordained canon.
If you don't believe me - that writing GUI code on Windows is a pain with Perl - ask the nice folks who have been working on "Padre" for the last few years. Combine a simple language (comparatively) like C# and a drop-dead-simple IDE like Visual Studio and, well, basically anyone capable of right-clicking and typing "Hello World" can make a network-deployable windows GUI application. That bar is set pretty high (I know) but I suppose the line has to be drawn somewhere.
"So -- let's face it. You win. You've proven you're better than everyone else here. You can leave, smug in the self-assured knowledge that you are superior, that you have all the right answers, and that you are better than me."
Smug? Maybe popping one's bubble for their own good will be misread as smug. Your skills as a competent Perl programmer put you in a great position to learn C# (enough, anyway) quickly - very quickly. In fact most of the "innovations" I've seen in C# over the last few years have been in Perl since version 5.0 came out or earlier. To me, C# seems to be stuck in catch-up mode, trying to mimic what's going on in Perl and Ruby.
And what's with all this "Oooh I'm not man enough to xyz" - popping this perceived vibe of "Perl is the only tool in my box so it's the only tool I'll use" in the OP - however rough and bruising to your ego it might have been - was probably necessary.