You really NEED to copy the procedure down and put it where you will be able to see it when starting programs.
The process is really rather simple:
1) While in the Presets tab, choose either a "Loaded" or "Shell" Preset.
2) If using a Shell Preset, move to the Programs tab and load the programs desired.
3) Move to the Control tab, click "Allow Generator Overwrites" box and wait for the checkmark to fill the box, then click a generator box that is red - meaning it is stopped.
4) Click "Start" button to start the generator running.
If at any time in this process you make a mistake, and don't know how to recover, go back to the beginning and start over.
Also, make sure there are generator(s) stopped prior to trying to set up new Preset/Program combinations.
For more details, please check the link: