by darkstar 1 » 20 July 2017, 23:57
Make a timer, change the 'delay' to 0 and let it activate a trigger, this trigger has the "Gameplay > Set gamespeed to 'A' frames per second (Defauld game speed is 30. Do not affects rendering)" in it.
Anything lower than 30 will slow down the gamespeed, anything higher than 30 will speed it up.
Also, I think the 'Questions' section on the forums is a better place to post/ask this.