I think I've figured out how to solve the problem that was preventing me from making more progress on Project Xenia. It's a little more work to fix than I thought it'll be, but this is a needed fix. As a bonus, the number of tiles per tile set will now be effectively unlimited (not that I plan on using -that- many, but it's nice not to have to worry about a limit). The downside is that I don't know yet what this will need in the level editor. I'm adding flexibility it doesn't handle yet.
The official server of XenoNet and the City of Elseways.