EXS 24 Logic Sampler Users Group

Hi everybody,
I remember someone mentioning a bug with EXS  and Quictime 
a few months ago.
I actually have a problem when creating my own instruments 
from aiff samples: the EXS edit screen goes suddenly blank 
(white),and when trying to go out of the window,all windows 
become white ! and then when i try to quit to relaunch Logic, i get 
an Error 2,loosing all my work.
Does anyone have the same problem ? and a solution ?
Thank you very much and pardon me for my poor english ;)

867 Quicksilver G4,250 Mega to Logic.OS 9.2.2