Erm... I think you meant fadecorpse, didn't you?
Here it is...
;Artificial Intelligence Script
;Header
desc = Fade Out Disappear
;Triggers
:state=0:state=1
:state=1,alphafadeequal=100:decalphafade=0
:state=1,alphafadeequal=0:state=2,sound=$0,destroy
;End of Script
That must work just enter sound in the FPI file.
If I misunderstood again, open the FPI you want and add sound=$0 before destroy...
Edit: If you want the sound to play earlier, set the sound command as the 1st action in the 2nd line (in ;Triggers)
For all my free FPSC entities!