Okay, some testing results thus far;
- The icon on the running instance in Linux Mint works now.
- I can set MC as the default application for audio and video on Debian and Linux Mint.
- However, on Mint MC sets itself as the default application for text files. I'm not sure what's causing this one as I don't see any text files listed in the MIME list, nor does it appear as a choice for text files on Debian and Ubuntu.
- I don't see MC listed as a default application option for music and video in my Ubuntu VM, even after running sudo update-desktop-database and rebooting. Hmmm, maybe I have a broken install, not sure. However it is working in my main Ubuntu install.
- After installing the .deb on Ubuntu Synaptic shows lame as auto removable. Is it not needed anymore? Anyways, I removed it and reinstalled it to get rid of the warning in Synaptic.
EDIT: Fixed the Ubuntu VM install, had to uninstall MC and reinstall it. Works good there now and it shows up as a default application choice.