Spent of the most day hacking on the Novus Map Editor (and the other applications!) but this was easily the most messy tool because it grew so fast, so I'm repaying a bunch of performance and robustness technical debt...
good news is that it no longer crashes while resizing the window and the materials look a lot better 
Here's Limsa, which looks a *lot* better although now way more laggy because I loaded everything at once...