When you know well what you are looking for, debugging is not that hard to handle. Damage boxes: either stored in RAM and make perfect sense, or need to be found by when object takes damage. Case 1 is already obvious, now how to debug hitboxes?
Set breakpoint on object's HP, it will work when he gets damage. If you pick that frame when breakpoint fires, and trace the code for that frame (from frame boundary accessed by frame advance, to when BP was hit), somewhere in the trace you will see how collision is being checked. You will see 4 points checked with other 4 points, being object and obstacle. If the game stores hitboxes in RAM, these points will be direct addresses. Otherwise you will see how they are made up. Normally X/Y point is taken and some offset is applied to form a box, according to object type. Later in the code HP gets actually decremented. It's very fun to figure these things out, and becomes very useful once you're capable of doing basic stuff with it (I learned it before tasvideos' eyes).
Instructions aren't hard to learn during practice. Just get a set of them.
http://tasvideos.org/ReverseEngineering.html
