First I'll say that maybee the engine might have been sitting around for some time without any after run oil and the old fuel/oil is gummed up the Barrel and it wont rotate due to being gummed up? (That looks gummed up to me from the photo)
A-Throttle barrel control horn
B-???Maybe a carb mount screw, cant tell from the pic?
C-Barrel stop (Idle adjuster)
D-High needle adjustment.

Altho the engine is new it can be gummed up and needs cleaning to free up the froze parts.

Hope this helps...I also reccomend hands on help with this...Don't try to fix it over the Forum as it will leave lots of room for error and you dont want that.
Shayne