Would like to get some advice from all of you so I can learn a little on
this before contacting
a Contractor.

Have a 25 yr old house in which the upstairs shower stall is one of those
molded plastic
types, where most of it goes in as a single unit.

It's about 6 feet high, which leaves the remainder to the ceiling, and the
ceiling itself, just
painted drywall.  It has begun to flake.

I am thinking of asking a contractor to come in and discuss the possibility
of doing the rest of the
walls and the ceiling with additional plastic.

a.  Is this feasible ?

b.  After scraping the flakes off, need there be any surface treatment or
priming (e.g. with that Zssner product)
     beforehand ?  Can the primer, if needed, go directly over the existing
paint ?
     (I'm assuming the drywall underneath the flakes is still in
"reasonably" good shape)

c.  If not in good shape, what do I do ?

d.  As always, there's always a complication.  The ceiling over the stall is
curved.  Not a plane surface that slopes, an actual
     curve to the outside walls.  Not drastic, but a pretty fair amount of
curvature.  If "plastic'd" over, can they handle a curved surface ?

e.  How should the joints be sealed ?  RTV Silicone ?

Any other options, thoughts on what else to ask the contractors, etc., would
be much appreciated.