shapeshift and epic creatures

[fl8m]

The sorcerer in my campaign has recently aquired the shapeshift spell, and her favorite tactic is to turn herself into either a Hunafer, or an Anaxim, the only 2 epic monsters they've encountered.
My question refers to the anaxim specifically it's got spell immunity as a construct. so what spells if any can effect it, also will greater dispel magic dispel the shapeshift effect?

Also I've ruled that when she's in Hunafer form she doesn't receive the +10 insight bonus to AC. although honestly it's more of a balancing factor than me having any good reason. my question is by the rules should she receive it?

 

[Dwarmaj]

If the insight bonus to AC is an Su or Ex ability, then they're suppose to get it. I'm not sure what the hit dice of a Hunafer is, but Shapechange has been errata'd to only allow forms of the casters "caster level" or lower, not twice the caster level that is listed in the PHB.