I use RPG System in my own game, so I made sure my mod was as compatible as I could make it. However, that is not perfectly compatible. Run speed leveling up works. However, like the message said, RPG System's run speed potions (enabled in the settings) will only work properly while THIS mod is in Fast "+" or slow "-" mode, NOT while in acceleration "<" mode.

Using a run speed potion in accel mode will seem to have no effect, however, it does silently start the internal timer for the potion's effect to wear off. If you accidentally drink a run speed potion in Accel mode, then you MUST wait the full 5 minutes for the "effect" to wear off before you can drink another. If you drink another before the timer runs out, another 5 minutes is added to the timer, and now you must wait a total of 10 minutes.

Thanks for checking, and see my other big mods, Satisfying Alternate Recipe System and Dysontorio Charging (inspired by Satisfactory and DSP)