I recently completed my first stripper, using MAS resin and slow hardener. I used 4oz S-glass from Sweet Composites. Prior to starting my layup, I re-read Rob Mack's great advice on Transparent Layups. My working temperatures and strategies were much the same as yours. I seal coated the bare wood, but did not sand the seal coat. I laid out the cloth when the seal coat was no longer tacky. I am very happy with the results, and feel that I achieved a transparent layup. There is, although, one exception: I chose to use a 9oz fiberglass tape on the exterior seam. The tape was purchased from a different supplier, and had a selvedge edge (I cut off the selvedge edge prior to laminating). The end result was disappointing in the wet-out of the seam tape: white flecks of unsaturated fibers are evident, and there are some minor areas that are not fully transparent. Although I communicated to the supplier my intended use for the tape, it is clear to me that the tape was the issue for the lack of full saturation. My cure for this is to distract any pixel peepers with significant scratches though hard use (actually, no one notices).

If you haven't yet, go to the MAS web site and read all the FAQ's and other info about use of their epoxy. I spoke to them a couple of times about another issue: static electricity when applying fill coats. Their first step of avoidance is, don't vacuum your boat, as this can impart a static charge. Also, as Glen stated, don't use a tack cloth. I made the same mistake on the bare wood, and MAS set me straight. The tack cloth was used lightly enough that I don't think I suffered any repercussions.

I was advised by MAS on the use of denatured alcohol, and what I will offer here is certainly open for comment and discussion! According to MAS, the epoxy can take on a static charge when it is packaged into the plastic containers upon manufacture. I wonder if this is why West Systems epoxy comes in metal containers? Since I was having obvious problems with static rejection of my fill coats, I needed help. MAS advised a light wiping of the kayak with denatured alcohol (I used new, clean, cotton "wiping cloths" from the paint store). The second advice was to add a very small amount of denatured alcohol to each small batch of epoxy during the mixing stage, as this neutralizes the static charge. It worked, and my static problems were cured.

It seems that given the problems that I had with the seam tape, perhaps your problems were from the cloth not being optimal for a transparent wet-out.