The rules for Pure require:

"No imported RCT1-2 track designs or other player-made track designs are allowed in this run, only the track designs built into the game. NG+ track designs are allowed."

Does "other player-made track designs" include not being allowed to use the coaster editor in-level?

Additionally, if you ARE allowed to do that, are you allowed to save coaster designs during the run for re-use later?

Sorry for the late reply.

You may use the coaster editor in-game, the no import means you cannot use pre-made track designs because I , personally, consider it cheating, which is why we made two categories. One that does allow player-made track designs, and the other that does not (Pure).

However, I would personally think that there is nothing wrong with saving a coaster design for later re-use during the run, as you'll need to dedicate some time to designing and saving the design, essentially negating the advantage you'd get by using a pre-made track right as you start your run.

Feel free to make designs and save them to build them down instantly in the Customs category. But the real plan for the Pure category is having a layout in mind and building it from scratch using the in game editor as fast as possible.

In addition, any track design saves made during a run don't invalidate the run.