The Deep Dungeon levels are by far the most annoying tasks that you'll encounter than any part of Tactics. I'm just trying to make it a little easier so you can actually see where everything is.
The maps are made to look like you are moving with the teleport on in total darkness. It's a good idea that you bring someone with the Time mage move ability "teleport" with you. During the battles you will be able to see where you need to go, and you can move your character that has "Move find item"(neccessary for getting the treasures and exits) to the correct tile with less hassle.
For viewing purposes its best you press L2 to zoom out and R2 to change the camera angle to a more downwards view.
The Red tiles are exits.
The Gold tiles are Treasures.
Blue tiles are normal tiles.