Game speed can only be changed +/- 5% using hotkeys

Hello! After updating to the latest 2.0 version on Steam, I've noticed that (at least in My Pet Dungeon) the game speed cannot be changed by more than 5% in either direction by using the hotkeys. You can edit the game speed using the ESC menu, but otherwise, the hotkeys won't get you more than 5% away from whatever game speed is set using that menu.

I'm running WFTO on Windows 10 x64 on an i7-6700k, 32gb RAM, GTX 1070.