#Can I change the number of stages?

Config.Stages.Count is the number the rest of the game reads (Teleport panel rows, skip pricing, the finish trigger's reset logic) — but changing it is only half the job. It doesn't generate stage geometry for you; you still need to build the actual Gate/stage-spawn parts in Workspace for any new stage number, following the naming pattern the existing stages use (Gate<N>, Stage<N> spawn point, and optionally a Gate<N>Safe if that stage has a boss arena). Bump the Config number and add the world geometry together, not one without the other.