As mentioned by et voila, there was a fairly major bug in the launching of native file (only on Windows) in 4.9.20. This bug was introduced inadvertently during the implemention of a feature requested by another beta tester, and we've moved on to 4.9.21, which seems very solid so far.

I don't want to sound like a broken record, but we are rapidly converging on a near-bug-free version.

We are tremendously grateful for everyone's dedication so far. We've come a long way since 4.9.0!