PK wrote:
Looking for some advice on what's best to do ...

I'm building a partition wall in a large room upstairs that is currently
open to the stairwell (a "game room") - the wall is 14 ft wide, 10ft high in
the middle for 8 ft and falls to 6 ft for a 3 ft width at either end.

No problem getting the carpet up, installed the sole plate along a floor
joist, attached the sides of the partition wall to the exisitng wall but the
header at the top of the wall is between rafters.

The ceiling is vaulted - ~8 ft in the middle is 10 ft high and that drops
for ~3 ft either side to 8 ft. I've installed 2x4"'s in the attic between
the rafters for the 10 ft high part every 2' or so but there's really not a
lot I can get access to (easily) to attach the parts of the header that will
be on the vaults.

Can I rely on it attaching at the top of the wall and the end of the header
at the 10 ft height?
Should I use some "no-nail" adhesive and a few toggle bolts and secure it to
the drywall and the top of the wall and the header?

Or is it simply time ot call in the city inspector and have him tell me what
is permissable?

All help appreaciated. In Texas, USA.

Regards,
PK

I would nail into your blocking where you can. then i think using
construction adhesive attaching the plates to the dywall would be fine.
of course, avoid splices in the plates where you do not have nailing.