With a new (beta) version of Windows Live Messenger (8.5) comes a new and improved A-Patch. If you've had problems running Messenger Plus! with the new version, then A-Patch is probably what you need.
It makes patching Messenger easier than ever before. Not only are there tonnes of options to choose from, but now there's a (rough) Preview which lets you see the changes as you select them.
User reviews about A-Patch
The download link is dead. :(