Will it be possible to fly it first with an IC engine and prop or DF in order to get "waiver qualified"?
A- Anything is possible but I'm sure it's not designed for that . DF would probably work. I think prop clearance would be an issue as a pusher. At least with thje intended LG length.
Is the retractable gear custom made?
A- Yellow was offering a sport gear for $140
How much do the retracts weigh?
A-They looked to be relatively light. Shouldn't be that much of an issue on an aircraft of this type.
How many servos are required? What type?
A- Best guess 7 . 4 primary flight controls, 1 speedbrake, 1 retracts, 1 brakes.
Are the wings removeable for transport/storage?
A- Yes, as well as the vertical stabs.
What will be needed to finish the kit aside from radio, engine, and standard modeling supplies?
A-Time and patience
Will the instructions detail making the speedbrake functional?
A-It is designed with a recessed area behind the cockpit for a speedbrake so I would think that they would tell you a little something about it.
Being Canadian, I'm not that sure about the experience requirements for the waiver. My feeling is that you might be barking up the wrong tree trying an IC engine on this thing. I'm also not sure about the term "turbine trainer" This airplane may be smaller and cute and made for a small turbine but I'm sure it will be VERY fast ! I'm building a Mick Reeves Super Reaper as my turbine trainer. A bit of a boat but it certainly will be managable and unsophisticated.