Mattrix,
You'll need to create your own programs to limit the number of channels/lights being used.
Here's how to program a chase.
1) Change the mode to "1-24 single"
2) Enter record mode (press and hold record button and tap buttons 1,6,6,8)
3) Create the first step of your chase using sliders 1-12. Press the record button and the display should then read step 001. Create as many steps as you need to complete your desired pattern. The controller will continue to display the number of steps you've created.
4) You now need to assing the created pattern to a flash button underneath faders 13-24.
Press and hold record, then press and hold the flash button. Release both buttons and your chase should now be saved (keep in mind that you have 4 pages to choose from, so make sure that you realize what page you're on).
5) Exit record (press and hold record and tap exit)
In case you do not like any of the patterns that you have created, you can always erase all memory and start off fresh. To erase all memory you must be in record mode. Then press and hold record and tap buttons 1,4,2,3 in sequence.
Hope this helps