They have found the problem, below is written by Glade Montgomery:
This is somewhat of a postscript.
It was not a quick process, and (since my Revo is now diagonally clear across the country from its manufacturer) it definitely required a bit of cooperative effort on my part. Regardless, we finally found a solution on the 912iS warm-start problem that developed about mid-way through my big cross-country trip (you may read above for details).
First, it turns out Rotax was purely innocent. The problem was outside their product.
More specifically, it was in a spade connector on a relay within the outside wiring.
The fuel-injection engine has two fuel pumps (redundancy in virtually everything). Until the engine is actually running, a different and separate circuit is required to keep those fuel pumps powered. And, it's not like in a carburated engine where a fuel pump might merely assist. For fuel injection, at least one fuel-pump running is essential. Anyhow, this separate circuit is engaged via a little relay. The symptom I had was that, when attempting to start warm, within fractions of a second of the cranking action beginning, both fuel pumps would shut off (there are separate lights for each fuel pump, which makes the shut-off rather obvious). With both fuel pumps off, further cranking was futile.
It turns out it's this relay that's involved in keeping the fuel pumps powered pending engine start, and one of the wires connecting to this relay, via spade connector, was not tight. The female-end of the spade connector was just a little slack. The fix, once this was discovered, was as simple as pulling off the female end, squishing it a little tighter with pliers (so the parts that ultimately clamp on the spade are nearer together), then re-inserting the spade (don't think anything sexual here, please). I tested afterward, and all was perfect. I am happy.
Evolution Aircraft contracts with Powrachute in Michigan for direct manufacture of the Revo. This company does superb work. With a tremendously complex aircraft, this is the one (and only), directly definable and operational defect I have encountered. It appears. when someone at Powrachute attached the seven spade connectors to this particular relay, that person failed to notice this particular female end was not really and truly tight when pushed upon its adjoining spade (again, no sex please).
BTW, this was the first time Powrachute ever built a Revo with a 912iS, which encompasses monumentally more external wiring as compared to the standard 912s.
Though the consequence was frustrating, I have to tell you I am really impressed that this is the "worst" problem I've encountered, from the very, very fine work done on my Revo.
I salute Powrachute for their excellent work, for the pride they obviously take in their work, and I further and even more strongly salute Larry Mednick, his dad Phil, and the whole crew at Evolution Aircraft for the intense dedication they have to this sport. I could hardly be happier. They afforded me a great adventure, along with further and continuing sublime enjoyment in my incredible aircraft.