Hi!

1. We left ours just as it came ... no thrust angles added (I think the firewall doesn't have it built in)

2. Several Hobbico planes come with that setup. I don't know of anybody that has ever had problems with it... just make sure you tighten well all the screws. It's OK for the metal-bars to "bend" a little ...

3. We used an OS 46 FX-H in ours and the plane came out pretty nose-heavy ... We didn't really care though, since the plane was a trainer!

...As you can see, we didn't do much except for putting it all together ... the plane flew pretty well and if I had to build another one, I would still avoid things like balancing (as long as the plane is a little nose-heavy) and right-thrust!