here are my 1st few attempts at cmyk drawings:

Im using Staedtler triplus fineliners as they where what i had on hand and they had colours close to cmyk

It was actually looking promising before I put the black layer on:

Then when I added the black layer it just took out any colour it was building up but the outcome was still pretty cool:

the layer order was C M Y K then I remembered when you screenprint CMYK you do it from light to dark so the order is YMCK (like the song right? =P)

so here is the second image I tried using a new order and it turned out much better.

registration was pretty easy as I just etched a line in the centre of the gondola and just matched it with the centre line on the drawing surface.

Wow VAC they look great!
I do indeed like the transformer!!

Here is my play in the CMYK pond,

Err yess... Butts... 2 Butts....

I did YMCK colour order for this and each colour started from a different corner.
The drawing was done on A3 watercolour paper (100% cotton) with the pes size set at 0.80 The cotton paper does not soke up the ink to much and the big pen size helps things from oversaturating (or thats what I'll tell myself)
Now I'n thinking that doing CMY with a pen size setting of 0.40ish so the colour is nicely saturated but then doing black with 0.60 or 0.80 so you can see the colour under it.. just an idea.