Odd! In theory, WinUAE shouldn't crash due to anything you've done on the Amiga side of things...
Does your PC have any strange hardware, specifically any odd SCSI devices that the emulated Amiga environment might be trying to poll?
Also, have you tried using a different version of WinUAE, or using the host filesystem rather than a hardfile?
And welcome to A.Org btw!
- Ali