The answer to number 4 (from personal experience) is that they do work, but not on the intended party
As for how to arrange mods, could I make a suggestion? Of course I can
, let me rephrase. Here's a suggestion : Have one download section (with a couple extra categories) and allow each mod uploader to specify which versions it works with (1.4, 1.5, both), possibly by having a checkbox for each version. Then allow searching (or viewing) the mods by which version it works with. I don't know if the download setup your working with would allow that, but I believe that would be the least confusing method of organization. If that isn't a possibility, then, perhaps, allowing a mod uploader to duplicate the mod in two categories.
Probably need to add an application category, too, to cover the applications that massage the game files (things like S3D, MultiSH4, etc.).
Just some thoughts
