Tile Access

Is there any way to access individual tile information on a layer?

I have a square object of varying sizes, and I want to get all the tiles on a layer that it touches. How can this be done?

I have tile collision enabled for each tile, and when I use CastCollisionList(), the value returned is just the object ID of the t2dTileLayer repeated over and over, e.g.:

1320 1320 1320 1320 1320 1320 1320 1320 1320 1320 1320