Vallejo Acrylic Resin Matte Varnish... Need Advice.

Over the last year or so, I have turned more and more to Vallejo products. I really like everything that I have used of theirs, so far, except for the product mentioned in the title.

For the life of me, I can't get it to spray consistently from my single action Paasche airbrush. The airbrush work like a champ with everything else, but not the matte varnish.

I tried it a few nights ago for the first time with mixed results. It seemed to clog the airbrush really easily. I usually run my stuff through at 15 or 16 p.s.i. It sprays Model Air and thinned Model Color just fine, with the occasional cotton swab (bud) swipe to keep the tip clean. I tried the varnish straight out of the bottle and thinned with Vallejo thinning medium. I tried both with a .3 tip and a .5 tip. I tried both combinations at 15, 18, and 20 p.s.i., but still got intermittent spray, and an easily clogged tip. When I broke the airbrush down, there was a nice glob of the stuff on the portion of the needle where the fluid comes out.

Anybody have any experience with this stuff? The varnish that actually got on the model looks really good and I really would like to use it, but not with these kinds of problems.