Optimus futures uses AMPIf you want to use TT with your new broker this would narrow the list that I posted before down to the following:
TradeFutures4Less (FCM is Dorman Trading)
RCG (through Sweet Futures as the IB, for example)
and maybe Optimus Futures
From these 3 remaining options, I would go with Optimus Futures, I am pretty sure you will get the best and most knowledgable support there.
You can contact the CEO, Matt Zimberg (MattZ) right here on Elitetrader, he is a sponsor and very helpful user of this site.