Anytime. About the tool, I know that there's a tool for editing day/night palettes somewhere... That probably also will add on he day/night sequence.
And in order to insert quite a few buildings into the tilesets you have to go to advancemap, load your rom, go to the place that you want to have the new building, and click the puzzle piece. Make sure you are in the right palette (color scheme, if you aren't your building wont have the colors you want it too, you can change palettes with the "palette #" button and check the colors on it with the "Palette editor" Then you click "tiles" (NOT BLOCKS, that would be bad, it totally and utterly destroys your ROM, trust me.) and click "save tileset 2" save it as "Tileset2 _____" and then open it in paint, photoshop, etc. And insert the tiles you want. Then you must recolor those tiles to the colors in the palette. If the colors aren't right, the tiles will be colorless blobs. Then, once you have edited them completely, you go back to advencemap, open up the puzzle piece, and click Tile>LoadTILESET2. If you click Tileset1 with a tileset2then your ROm will blow up... I think the new Advancemap Beta has protection against that though... anyways, don't do that. Then those tiles will be in the tileset (the lump of junk to the right) and you click them and put them into tiles on the left. And then you have a building (or anything, actually.) you can use.