There is primary and secondary binding for each action.
When you bind any action, you bind the physical key to the action; you do not bind a letter. This is to make things easier for players with different alphabets and keyboard layouts to set up their game correctly and start with the same control scheme we use by default.
Limit for binding one action:
2 keys + 1 mouse action
The same key binds cannot be used for different actions
There can be the same binds for world and menu actions
Once the same bind is used, the old one is marked in red color
Keyboard forbidden keys
Esc
Win
Fn (laptop)
Mouse allowed buttons
Left mouse button
Right mouse button
Middle mouse button
Scroll (Up/Down)