I think that by "spindle override" you are talking about the speed increase slider on the main screen that (on my version) is just below the feed rate slider override. That is indeed at 100% and I used it to increase the speed during the testing I did to create the above chart. It is proportionally correct. If I set my rpms at 5000 then bringing the override slider to 200% doubles the speed up to 10000 rpm.
Thanks Gerry,
BH