I looked in the game rules in any% and it says switch FW versions later than 10.0.0 are prohibited. if i want to Fast action guide skip i must show my FW versions. What does that mean? Am I not allowed to use versions later than 10.0.0 or have I to show my FW version after the run?

You have it backwards. Versions later than 10.0.0 are allowed. Older versions are prohibited.

Thanks for this information!

If you'd like more information, this announcement https://bit.ly/3sVYaVZ summarizes why the firmware rule was implemented.