WindowMaker

Could anyone tell me what the
+COMMENT
+CONTENTS
+DESC
+MTREE_DIRS
Files, which are installed by windowmaker, are used for. Additionally would there be any negative impacts of hiding them or removing them.

I've noticed those files as well, but wouldn't suggest removing them. I keep Mac OS X on a separate partition to keep the files out of my way while booted in Mac OS 9.x. Those files should be invisible in OS X, unless you're logged in as root.

You can try placing a "." in front of the filename to hide the files in Classic. However, this may cause problems with WindowMaker.

Unfortunatly they're not invisible... I think they need to begin with a "." instead of a "+"

You can safely remove those files.