Hi and welcome to the forums!
What Elliot said is correct, but I'd like to add that not everything can be rotated - objects that aren' symmetric just wouldn't look right seen from a different angle. Unless you had several different views per object, in which case you would have to switch images when rotating. Also, moving characters around following a rotation may be a bit confusing, since the direction suffixes for character animations (n, s, w, etc) would have a different meaning.
Another consideration to do is that rotating a tile uses some memory (a new image has to be created), so if you have many tiles and this is a problem, you may want to unload the previous tile images (with wade.unloadImage).
Anyway, overall it's a bit tricky. And this has come up a couple of times in forum threads, so we should probably consider adding built-in support for rotation in the next version of wade.iso.