All in-game graphics are normal, but the SEGA 60th Anniversary splash video does not appear upon start-up.

• Keyboard input works as expected, once the input mappings are added in the configuration window. (Note that some actions are not mapped to keyboard inputs by default; this is not a Proton issue.)
• Playing with an Xbox 360 controller mostly worked. However, pressing the Start button during gameplay added a second player character, also controlled simultaneously by the same Xbox 360 controller. I found that I could use the keyboard to control one of these characters, but the single Xbox 360 controller would still control both of them at once.
• I plugged in two controllers to try multiplayer. The first character was controlled by the first controller as expected. However, pressing the Start button on the second controller resulted in the addition of two more characters, both controlled simultaneously by the second controller, for a total of three characters (or four characters if I had already created a duplicate character with the first controller as explained above).