Freezing on the opening intro has been an issue since release, it's a limit of the framework which is not being updated. You have 15 seconds to skip the opening intro with A before it'll lock up.
As for the No Encounter cheat not always working, please provide as much detail as possible so I can address this as I cannot replicate the issue.
This will be fixed in the next update.
It's super easy to change. The line of code that dictates which button is used is right here:
https://github.com/AnalogMan151/sumoCheatMenu/blob/master/Sources/movement_modifiers.c#L58
It can be changed to any other button but I'll consider making it a toggle. I never thought someone would use it so much that it would wear out their button. The reason it's not now is that R is used in other cheats and it would be weird to use R in another cheat, then suddenly find yourself walking through walls because you also had the Walk Through Walls cheat on. So I may make it a multi-button combo.