Nice to see that you got your desired result in the end. Inhibitor is a very useful tool when working with polyester, and most people don't know of it's existence.

Quick Update . . .

I wanted to close things out on my extended swim platform project, which is now done.  Here are a couple of pictures of the final result mounted on the boat.





The TBC inhibitor worked well to allow a good 75 minutes of open time for the mold infusion.  I did use MCP catalyst on the actual part infusion rather than the TBC.  I ended up infusing the outer layers of the part, but then switched to hand layup for the core and inner layup lamination.

The resulting part (i.e. platform) was surprisingly light (100 lbs w/out hardware) and quite rigid and strong, which was a goal of mine so as not to add too much weight to the stern of the boat.  I'll be testing it out for real over the next few weeks

It was certainly a learning process for me, but I am pleased with the results.  If I had to do it again, I could probably do it in half the time and half the cost.  So, there is the price of learning, I guess.