Sorry to post this. Somewhat hard to reproduce, observed in 1.8RC5 and also 1.8RC4 on Win7.
1) Open and close multiple images, use auto STF, zoom and pan.
2) Run Blink script, add and delete multiple images, zoom and pan.
3) Open Deconvolution process dialog, select External PSF, choose view. View is a 7x7 n1 f32 Gray image of a Moffat PSF.
4) System Exception alert.
Mike