Ok, I think I see what's going on. It took me a few tries to understand your problem. In system, there isn't actually a "rotate layer" event, only "set layer (or layout) angle". The angle you tell it is a fixed angle. It's not going to rotate.
So try this...
On touch object, set (system) layer to "LayerAngle(layer)+90"
where "(layer)" is the name or number of your layer. So for instance if your layer is on layer 1 (that's the actual number identified by C2 on the right hand menu) you would have "LayerAngle(1)+90".
Now everytime you click on the object it will rotate an extra 90 degrees.
Is that what you meant?