Can’t set data sources for Movies or TV

I’m working off of the most recent stable release, and I’m not able to add a data source for either the movies or tv. When I click on the (+) button, the Finder selection window pops up, but the ‘Open’ button stays grey until I click on my source folder. Clicking ‘Open’ then drills me down into the folder instead of selecting it. The only way for me to get out of this is to click ‘Cancel’.

I decided to modify the config.xml file, but after saving that config and starting tMM, I was taken into the setup wizard, and my previously configured data sources had all disappeared! Attempting to run through the wizard resulted in the same behavior as described above. I feel like I may be missing something really obvious, here…please tell me I’m right.

Also, why does manually editing the config file result in it getting wiped and launching the setup wizard again?