Optimizations Part 6: New Sprite Loading System for 30 min Exercises

* New more effective sprite loading system added for 30 min exercises at all levels. Only the 40 min and 1 hour workout algorithms to change to the new sprite loading system now. Once I get these done I have an idea of how to put a stop to some players' AV checkers from flagging this game up as a false positive. Thank you to players for letting me know that this new sprite loading system has beaten the blue bar/time lag bug/glitch. Fantastic news!