well the element way that i use would be, asuming that you have already recorded a intensitylevel and just need to remove color/focus data from the sub
Blind
Sub xx [enter]
color, focus [@] [enter]
Live
color and focus are soft keys on the element, I cant recall the steps to record only intensity unless i am sitting at the board doing it.
How are the patched? Are the patched with a dimmer, or are they standalone? Since they're a scroller, unless they're associated with a fixture on a dimmer, there is no intensitychannel to make a sub with.
There are a couple of ways to do this... you can record only the intensity to a fader, so that the intensity is the only parameter that's in that fader... (ex. channel 1 intensity {hold shift (or the follow/hang hard key if you have an older ION) and tap either custom or shutter to put intensity on the command line I can't remember} record sub 1 enter) or if you already have a look or fixture stored in a sub than In sub edit mode (tap sub twice) change your mode from proportional to intensity master. No matter what fixture are loaded on the sub, the fader only controls the intensity. I use intensity masters a lot when I want to manually mark something, which sounds like what you want to do.