Power FC question

[Rittmeister]

Just picked up a PFC from the good folks at RT Tuning; installed it yesterday.

Setup is: redtop DET, stock turbo/boost/fuel/air, except for big intercooler, big exhaust, and Walbro fuel pump.

The car ran great with the stock ECU. With the PFC it starts up, idles, and drives fine EXCEPT that it bogs on tip-in when starting from a stop. If I rev the engine out to 4-5k before shifting, no problem, but if the revs drop below 2k or so it also bogs on shifting.

Here's the weird part - the problem completely disappears when the car warms up past 50*C or so. I mean completely, not even a hint of the issue.

-Timing is dead on where it should be.
-Car doesn't leak vacuum or boost that I can tell - holds vac on the gauge perfectly. Admittedly I haven't built a pressure tester to check this but as it ran fine with the stock ECU I see no reason to believe there's a problem.
-Plugs, TPS, fuel pressure, other stuff is fine.

Basically, has anyone had a similar issue, and if so what was the solution? Is the PFC an adaptive ECU like the stock ECU?

Also, on a side note: the PFC doesn't have a provision for mounting the stock ECU bracket. How are you guys securing the ECU itself inside the kick panel?