Duck and Cover

Some times when I try to beild a roof I see that the size of the room does not much the tiles and so to make a whole roof I have to make the tiles overlaping one eachother. How do I fix it?

Don't overlap the tiles! First thing to do and it should be in one of the tutorials, is to set your floor level on a level like 0. Then go to level 1 and start placing your walls on the edge of the floor tiles. Then as a final step at level 13 place your roof. The easy way is to show tile boundaries so that you can see the edges of the tiles, like this:

That pic just makes me wonder... Notice how some tiles are highlighted specially? The stair are yellow, windows are purple and the ethereal tiles a gray... Also if you look closely, you'll notice the tile bounding box is actually semi transparant (like my viewer .

I wonder why they removed all those features as they were actually quite handy.

All that stuff is still there Red under the View menu:

Show Tile Poly
Level Ghosting
etc

No.

The tile bounding box is NOT semi-transparant like in the pic (well only the "Active" tile which the guy's is highlited that way in the pic really) and the tiles are highlited by level but NOT by type (ie: stairs, ethereal and window tiles don't have any special colour).

Flag Coloring will highlight windows, etc with a different coloring. Not sure about transparency.

Yey, I've learned something enw about the editors! Thanks JJ Maybe it was obvious but for some reason I missed that. Actually, I know why, it's because in my previous maps I didn't "update tile data" (thanks to OTB for that one though I think most mappers could have pointed that out to me here) or whatever and toggling the flag colouring didn't seem to do much with no flags enabled...