If it's going REALLY slow, you probably copied your mm/sec values from your other software. Everything in Creator is in mm/min, so multiply by 60.
Here are the places where you set up speeds:
When you add your "Process" (FFF), double-click that to open up the FFF Settings window. The main printing speed (again, mm/min, not mm/sec!!!) is on the "Other" tab. A typical value for the M2 is 4800 mm/min (80 mm/sec). Also here you find the X/Y movement (fast move with no extrusion) speed (M2 typ. is 12000 mm/min (200 mm/sec)), and the Z move speed (lift, between layers, M2 = 1200 mm/min or 20 mm/sec). Extruder retraction speed is on the Extruder tab (M2 = 1000 mm/min).
The stuff in the Firmware Configuration and General Configuration under the Tools menu is the G-code commands used for various functions and stuff like the build envelope size. Nothing here on speeds. It's all in FFF setup. And all the other speeds are in percent of the above (like first layer speed, that sort of stuff).
Oh, one more thing: (I hope I'm correct on this!!!) I believe all the G-code values are in length and time units (mm, etc.), not steps. Everything to do with "steps" (converting mm to steps) is done in the firmware, not in Creator. You build the firmware with the steps/mm for each axis as a parameter, so the printer itself "knows" how many steps or steps/sec to move when you give it a distance or speed.
