alt R does work. sounds like it's not working because you have a windows shortcut or something enabled for alt R. afaik there is no fps counter in game.
5 days ago(+2)
There is, but it is just a part of your HUD you can't turn off without hiding everything else.
Control buttons can always be reassigned. For example, I used to open the NVIDIA panel by pressing Alt+X, but I reassigned it to Alt+R as the rarest key combination, since Alt+X was also used in some game. But in this game I encountered this combination and simply reassigned the Alt button to an additional control button on the mouse - very convenient if you need to throw something on the run, for example.