I worked on a rig for the most part made up of
LED pars earlier this year, and controlled them off of a
strand 500 series
desk.
From the sounds of it, you don't need the
intensity channels on your fixtures to actually do anything, (which is a simmilar situation to the fixtures we were using).
Basically the way we got around the whole profiling of the fixtures, was to just create a basic personality with
CMY attributes (I don't think there are
RGB attribute numbers, either that or it just made sense as everything else we were using was
cmy) as well as the three colour channels, we also had like some channels for macros and stuff, so we assigned them to the relevant attribute numbers. Without the
intensity channel the fixtures weren't visible in the normal
channel display, so we just patched an
intensity channel to an unused
DMX output (this wasn't part of the personality, just 4.1 @Patch 203.1 where 4.1 is the unused
DMX output and 203 is the
fixture number).
This does mean that the lights can't be controlled by one
channel alone, but if you set up some groups (i.e. 3 colours off, red on, green on, blue on and combinations there of) programming isn't really any slower than it would otherwise have been and the only potential problem is that the channels would be using the
LTP times instead of the normal times that the rest of your
intensity channels are using.
Hopefully thats the easiest way to make a 'dummy
intensity channel', just make a real one but direct it somewhere where no one will notice it (by no one I mean none of the lights, they're people too right?)
Hope that helps.
Diarmuid