File quality 7.00 and lower screenshot creation works while 7.13 and higher does not using ksp_64.exe. Screenshot creation attempts crashes ksp.exe twice in a row so I don't think its based on the quality settings. The quality setting slider increments are not the same between ksp.exe and ksp_64.exe. I'm not sure how useful this information is or if this is known, but this issue list is the only place I know to look.

version 1.1.2