Hello my first question is : how can I make that an item dont get refilled when I pick up the Powerup-dispenser?

Second question :

I added trainmasters "manned dropturret" on Mos Eisley the turret looks normal but on DeathStar it looks like here : How can I fix that? thx

For your second question: Are you sure you have munged the textur of this turret too? Or is your turret on Deathstar exactly the same on Mos Eisley. If objects are white (or grey) a texture is missing.

@1: look in the powerup dispencer weapon. It's the only thing i know that isn't refilled by the powerup.
@2: the legend is right.

The turret has only on DeathStar and Geonosis this white "skin" and yes the turret is the same