Another bug! However, before I describe that I wanted to follow up on the Rune Dancer "bug." I saw this again, but with another unit. A total browser reload did indeed do the trick.
New bug: I'm currently playing two MP games. In MP1, I bought an Elf with two Hero Coins, but didn't like what I saw, so I closed the window to decide later, went back to the main menu and entered MP2. The first screen displayed was the Tavern with the three Elf options, which was amusing considering MP2 doesn't have any Elvin towns.
Worse, it won't clear, even with a browser reload, which means no buying new Heros in MP2...
I'm going to open MP1 again, select a Hero, and see if that resolves it.