well, I just assembled a pretty much scratch built foamie, When I started out the first flight today, it was very unpredictable, rolling out in loops and everything. It was tail heavy, I moved the electronics foward and got it a little nose heavy and that helped. Then it still roll out in tight loop, the wing was twisted, and I can't fic it in the foam, it won't stay. You said your is rolling out, try checking wing for twist. If it is not then make sure the rudder and vertical are straight, roll out in loop could be a rudder trim issue. You said the stabilizer was all level. Was that to the wing? is it twisted through the fuse, no twist at all, you can look from front of wing and see that stab is perfectly parallel with wing. Then make sure wing is square on fuse and that the stab si to, if it is then give it thrust to the left or the oppiste direction of pull when taking off.usally the slower you go in a loop the more it wants to throw or drop a wing out and then spins out. Make sure it is balenced latterly to, not just CG being right, But like I said, check everything for square that I mentioned, if anything is off, fix it, go fly see what happens. If problem persists, toy with CG a bit, see what happens, move it both directions, in small amounts, try forward first then if it gets worst, try backwards. Then if nothjing happens, toy with thrust. But the diving problem still exists, maybe you have an incidence problem in the wing or stab. Is it heavily wing loaded maybe, maybe its to heavy somehow. But that seems like a CG problem. All I can say beyond what ive said is to toy with things, Everything I have mentiond fixed everything of mine that had problems. So Good luck