Well, this is certainly disappointing. There used to be several guys around here who knew about these things, or were willing to test them. I guess they've all moved on. Where's Axcel216 when you need him? Oh hell, I'd settle for Problemchylde right about now :)
Looks like I'll have to test these files myself. The latest unofficial "update pack" for XP that I found was XPSP3_QFE_UpdatePack_20170619. It's designed to be "slipstreamed," so the files don't need to be patched.
Inside was a newer version of GDIPLUS.DLL. It's a Vista file. Version 5.2.6002.24064. File date 02/13/17. 1,753,088 bytes.
It seems to work under SE. There are no missing dependencies. Of course, ti wouldn't register, but I don't believe any version of GDIPLUS will. My network works. I've got Internet access. As far as I can tell, it hasn't screwed anything up yet. Looks like it's safe enough to test.
I don't rightly know what GDIPLUS is used for. I believe it's got something to do with Visual C. I'll be sure to let you guys know if my machine blows up :)