One problem would be the classic Windows style. In Messenger 2.0, there were no UIFILEs, but now we have to use UIFILEs for our GUI. So you can't say: "Hey there, Messenger GUI Engine! Can you please f*ck off with your UIFILEs, I want to use a simple Windows style without those fancy PNGs and stuff!".
Of course, you can make a Windows 95-alike window using UIFILEs, but it won't take the style from Windows itself but from the GUI. But I think it'd look cool to have an old looking Messenger running on Vista, so I don't think that'd be a problem.
I
may want to try this, if I really don't find any inspiration for a skin. At the moment, I'm at the point of "What shall I try, and what can I do?". I already tried to install Wave11 MSN for 7.5 to extract the resources and attempt revive it but the UIFILEs were unreadable (i.e., no line breaks and I cba to add them).
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