Be ready to have an engine failed after you are established on the glideslope. Be able to explain the conditions used to find Vmc. Know the reasons that there is a critical engine. Know the systems to the airplane that you are flying really well. There ya go, that is really about all there is to it. Read through the PTS and be sure you can do everything to the standards. They can't ask you anything that isn't in there.

Failing a checkride due to a hinge on the door is BS. If something like that happens, say that you saw it during the preflight, and as PIC, you deemed it safe. If that doesn't work, call the FSDO and complain. Assuming that it isn't a safety concern.