If you remove all panels (/ other objects) that you've created after the game_save before you load the file again everything should be fine. The problem in not doing so is that the load instruction simply will fail because of a different number of objects of each type (I don't know if things like removing the oldest panels instead of the newest panels could work too so you have the same amount of objects, there may be other problems with different C_LINK index values and so on, you'd have to test that).