Update - Did a bit of testing. Hadn't had the ignition on in a few days, but when I turned the key, the "euro" switch worked fine, all functions work, headlight/dimmer works. After a minute or two, the switch would not work properly. Lights would not come on, blinking telltales, high beam telltale stays lit even though headlights aren't on, etc. This was the issue I had before.
Possibly low battery? Enough juice when you turn the key, but after a minute, not enough to work?
I put a brand new BMW battery in the bike about a month ago, and connected it for testing. Maybe something drained it?
Possibly a loose relay? Or, when ignition is turned on, power starts to flow through something, causes it to heat up, after a minute or so, connection breaks?
I'm going to let it sit for a day or so and try again to see if I get the same results. I want to check the relays to make sure they aren't loose, etc.