KE6VJQ -- the mount angle & offset is correct as far as Hobbico is concerned. However, I have found that the Nexstar flies better with the engine aligned more north & south.

I have encountered one Nexstar that wanted to do nothing except turn right -- which it did until it met Terra Firma -- Hobbico replaced it under warranty & their assessment of the remains was that the right thrust was incorrect.

The other Nexstars at our field also had substantial right thrust, down thrust, & left engine-mount offset (that's what keeps the spinner centered). They all flew acceptably well at relatively low power settings, but wanted to turn right at full power. All have had the right thrust reduced by putting a popsicle stick behind the right-side of the engine mount -- with the screws passing through the stick. They flew much better at full power. One of them has had all right thrust removed & the mount re-centered -- it flies very well, with a slight tendency to turn left on take-off & in vertical (upward) flight, as airspeed bleeds off.

I hope that this helps.