Homebrew PCBs

Well, I tried diluting and airbrushing some of the ink (white) but 
didn't have any success.

Well, it dilutes ok.  It airbrushes fine to a thin coating.  And I 
"baked" it in the oven at 180 degrees C for about 20 minutes and it 
"dried" ok, soft but tack-free.  Then I tried to cure it under the UV.

But... it doesn't seem to cure under the UV at all, something is 
inhibiting it, it can easily be scraped just by gently rubbing your 
finger nail on it or even just pressing your finger nail on it, there is 
no difference between masked area and exposed area. And meths on a cloth 
just wipes the board clean with no effort at all.

The alcohol I'm using is just Methlyated Spirits (>= 95% ethanol, and 
the rest water with a tiny amount of a bittering agent)
The UV cure I gave up at 30 minutes, no change in the hardness or 
fastness was particularly noticable, it was still "soft".
Hmm, I notice on the referenced site ( 
http://nicadrone.com/index.php?id_cms=24&controller=cms ):
   "Dry the paint in a reflow oven, drying temperature influences 
exposure time drastically above 100C "
it doesn't say in which direction it influences, perhaps my drying 
temperature is too hot and this messes the exposure?

So in short it would be really great if Andreas (ctech) could give some 
brief details...

   1. your board shows a soldermask (green) and a silkscreen (white), 
which paints exactly did you use for these?  Just the ebay ones, one 
green and one white?
   2. what type of alcohol did you use specifically, ethanol, 
isopropanol, methanol...?
   3. what temperature and time did you "bake" the board at to dry it?
   4. are you doing anything else before exposure?
   5. how long as you exposing the board for to the UV under the mask?
   6. what type of UV source are you using, and are you using any fancy 
things like a vacuum system?
   7. how are you developing it after exposure exactly, with the same 
alcohol, with sodium hydroxide...?