Just in case some applications depend on it. So far noone cared, at least regarding bug reports.
So far Wine has never had an implementation of region deserialization functions, so how could anyone have complained about it?
Current GdipCreateRegionRgnData implementation fully supports data generated by GdipGetRegionData, and I don't have an intention to pollute the code with useless FIXMEs. If you have an application that doesn't work with my implementation then just file a bug report and I'll have a look.
This is using FIXME's for their intended purpose, namely highlighting missing features when applications use them. I'm trying to avoid a situation where an application uses one of those features and a developer wastes hours tracking down the bug when we could have made it obvious for them.
It's nice that you're willing to support your code, but that doesn't help if we can't track the problem to your code to begin with.