Suggest the following:

First trim for straight and level, whatever your cruise speed is (normally half to 3/4 throttle). This includes aileron and elevator trim.

Next, thrust should be checked by pulling up to vertical from a left to right pass, then from a right to left pass. If the plane goes out the first time then in the second (after climbing verically) you need (more) right thrust. Let go of the sticks when you do this- if it pulls to the canopy both times you need down thrust. My extra, and cap pull to the Landing gear slightly, so I add up thrust.

Finally point the nose down, if its still pulling out as you describe, add mixing- down elevator with low throttle... its easy on JR, just three steps- Throt- Elec (1), page to next screen and hit "orig" (2) and finally, give 3 clicks of throttle stick, hit "offset" and then bump up the % to give you some down elevator.

This will help your down lines, and also the half cuban 8.

Normally don't need to change wing/elevator incidence or CG if its set to the plans/ or factory settings if its an ARF.

Let me know if it gets you set.

Cheers,

Don