RE: Which one!!!!!!
i think adrenalnjunky has some great points. the only things i'd add are:
increase take off speed - unlike a trainer or your gasser, a glow acrobatic plane of this size will need to be travelling much faster before it's ready to take to the skies. this would explain the wing rocking and the stalling. use more of the runway. this is even more important since your plane is underpowered with a 46la
check your elevators - make sure that they are even when they are at neutral and deflect at the same rate. i've had planes that planes that had uneven elevators. i'd trim ailerons for a certain speed then once i changed the throttle, the plane would roll again. was frustrating but eventually with the elevators even, it flew wonderfully.
richen the mixture - although i assume that the engine is broken in from your trainer and that you already have some experience with glow engines, remember that you need to richen the mixture a bit so it doesn't lean out when your flying at speed or climbing at a steep angle. i'd recommend the vert test before every flight
err on the side of conservative CG - you're cg is "right" may infer that it's within the range of the manufacturer. however, i'd suggest that you try a more conservative CG at first (more forward) while still in the manufacturer's range and move it back as you get use to flying it
and last but not least
don't think that it's easier to fly a small plane - it's not that big planes are harder to fly, they are just much more expensive and far more dangerous when out of control so beginners generally don't fly them. so don't think that because you can do some stuff on the larger planes, that it will translate directly to your ability to control smaller planes.
and to add to those that recommend a different engine. i completely agree. i think the 46LA is completely out of place in that plane. you should at least have a 46FX or AX. but as someone mentioned before, if you've got the money, i'd suggest an O.S. 91 or a Saito 82~100 fourstroke for your purposes. i'd suggest a YS63 but i'm afraid that's probably going to send you into a tizzy trying to get it to run right.