There's this time dilation feature available in tpt ultimia mode (as bowserinator like to call it)
Also, if you just want to slow/fast simulation speed there's a "tpt.setfps(value)" command.
(Setting it to higher values might not work if your pc is old and crappy.)
Of the changing time speed key,can be ctrl+f
Ctrl-F is already used, for the Find Selected Element mode.
So... Ctrl+Shift+F?