Remove admin mode requirement from FX3/TPA, and cumulative bug fixes for PinballY

Admin mode is no longer needed for the Pinball FX3 and Pinball Arcade "memory grabber" interfaces. Just run dmdext.exe like a normal program. This should greatly simplify front-end setup.

This version also has my cumulative set of bug fixes for use with PinballY (which will probably also help with other front ends).