That's exactly the problem with the Maddog. If an airplane has custom doors, GSX doesn't have any way to know if they are open, unless we can support it at least at Level 1, which means measurement+custom doors support.
We are adding a global switch in the next upgrade to ignore doors and go ahead, to fix these cases, but at present time, you can't really use the Maddog when using services at parking. You can of course use it for Follow Me, Marshalling and Pushback.