As of the posting of this message, these rules apply for every category:

• Changing framerate using a third-party program (e.g. Dxtory, RivaTuner...) mid-run to perform specific tricks is banned. However, you are allowed to switch your refresh rate through the game's options during your runs.

If you are looking to use refresh rates that your monitor doesn't support, such as 20 Hz and 144 Hz, you can now use the new version of the Windowed Mode DLL available over here: https://www.speedrun.com/trl/resources