DSOQuad SYS File Compiling Issue

I have downloaded SYS1.50 and APP2.50, I had make some modify to APP source, successively i have recompiled it and it work fine.
Now i must to do some modify to SYS file, before modify it I have tried to compile the origiinal source code to view if it work fine.
The compiling result is positive, but when i download it in to DSO, the lcd remain white and it don’t work, i think that the processor is working because i can listen the beep.
Have you some suggesion?
Sorry for my bad english, i’m an italian user…

wrong optimization settings

Thank You, I will try other settings…

With no optimization it work fine!

Thank You a lot…