Today I didn't get much done. I noticed that there are some problems with generation routines, because a mask data of tiles don't work. Mask value for tile is useful feature which I'm going to implement for Teemu the same way I have in Kaduria. The mask system has two types of masks, a regular type for terrain tiles and room mask which is a number given to a room or other similar type of area.
It's sometimes useful to assign mask values to tiles that aren't that tile's default type. For example in situation where you want to exclude a part of level from creation. Room masks are also useful, because then you can create stuff in a specific room, and when you have assigned only tiles of that room to a mask id it's easy to find tiles of that room later during the generation process.
I didn't have time to program that feature yet, but I'm planning to put that into Display_Map class which is re-created for each level when you enter it. That way I don't have to store mask values in each level which could be useful in some cases, but I think in this game it would just waste some memory.