My suggestion? I'm not a programmer (as evidenced by how bad my VBA is), but I was suggestion simplifying the specification. From the screenshots it looks like the angle of rotation is variable, so I'm assuming it's calculated based on the relative elevations of the tiles around. I imagine calculating it must be a pain to work out especially when it's not going straight up the hill. But I imagine it'd look fine if you just used assumptions in the angle.
Nontechies trying to help is probably annoying, sorry if I'm wasting your time here