Ah, the encyclopedia is just a little slow lately.
Mapping is "relatively" easy, in that once you load a location, you click a tile on the right with your mouse, and then if you click on the map, it will lay down that tile. Then, to save, you go to Locations > Write to Memory, and then File > Save.
But it gets complex after that. There are three layers out there; layer 2 is the background, layer 1 is the foreground, and layer 3 is lighting effects. Layer 1 is mostly objects, like chairs. Anyhow, it matters because whatever layer is checked under the Locations > file thingie, is what layer you will be editing when you lay down tiles.
Then, things get more complex because walls need to be solid, height needs to be handled, and stairs...ugh, stairs can be a nightmare.
But that's not the most important thing right now; we just need someone with an eye for aesthetically pleasing stuff. Solidity and z-plane can be polished later in the beta phase. If you want to map, just load something up and try it out. I added a little extension to Crono's room as my first act in Temporal Flux, with a table and some chairs. It's an easy learning curve for laying down tiles.