We've developed this list of simple rules to make level exchanging a convenient and pleasant experience for everyone. It is no way a final list as we hope that this forum will evolve, and we're always looking forward on your ideas and suggestions!
1. A list of requirements for levels package. 1.1. Each level must be valid and solvable, with Author name specified (Level tip is optional but highly appreciated). 1.2. If your package consists of more than one level, create a folder and move your levels there so you'll share a level pack. 1.3. Place your level or level pack in ZIP archive (Do NOT use other archives (like RAR) or self-extracting archives!), so other players could immediately play your levels after extracting the contents of your archive in their 'CustomLevels' folder. 1.4. As long as you're making a level pack, not a single level, try to make level titles short. Level pack title can be longer and more descriptive. As you probably noticed - level packs and levels listboxes in Custom Level Selection menu of the game are pretty compact, so try to optimize your level pack/level titles to look nice and descriptive at the same time in them.
2. Posting a new thread. Post a new thread only when you have a levels package to share. For any other topics please use other forums.
3. Posting a reply. You can post a reply to a thread with comments on the levels posted by thread author, or you can just try to ask for solutions for these levels.