I seem to be having troubles actually getting this to get along with DOSBox and ScummVM. Every single time I run something that uses the CoolSoft MIDIMapper it says it can't find a device and asks if I want to set a device. I can manually set it, but I'd swear everything is just reverting to the MS GM. Regardless, it's causing problems the way it forces me to reconfigure it every single time. I think the delay that this causes makes it not work right as the software does not expect there to be a delay for the MIDI device simply to respond during just initialization.
I'm using the VST MIDI driver btw. (Yamaha S-YXG50 VST to be specific.) It provides two ports for whatever reason. I've set it in the control panel separately hoping it would keep this setting across everything, but everything that uses this (ScummVM, DOSBox, whatever) always makes me select again anyway.
This is in 8.1 btw.