Good post!!! Good Idea!!!
I was actually going to do this myself but you beat me to it.
Firstly, I'd suggest change your title from "read before post" to "All custom maps have purple walls and ERROR"..that way anyone who is "genuinely" looking for help on that issue can see "someone else asking the same question". Once that is stickyed and remains at the top then it will be a good resource for newbies.
Secondly, if you send a nice forum message to iLL (forum admin) and request to then have this post made into a sticky, he can get that arranged for you. Unfortunately, as moderator, i'm unable to do that myself. Admin privileges lol! He doesn't trust me!