Yes, hit space bar on the tiles menu, and the tile selection radius should change from highlighting entire rows at a time, to highlighting a rectangular area instead. THAT's where you hold Alt and press directional keys in. Sorry if I was being confusing.
And by "one level up," I mean, leave the "drawing" screen and enter the tile selection screen, where all the tiles are displayed.
EDIT2: .. We .. REALLY .. need "official terms" for these, apparently. @_@'