Have a STi camera that is used for auto-guiding normally but also as an imaging camera for fast image collection for solar hi-res Ha mono imaging (collecting many frames and stacking). I noted that if you run it from CCDops (has latest update....I verified both it and latest SBIG drivers) there is an issue with it hanging when doing auto focus. It works fine with say a 2 second exposure and 3 second delay between shots....but if you set it to a fast exposure like .01 and an update of around 1 second...you can't pause it with the normal pause button. The only way to get out is to use Ctrl F. Not only that but when it freezes it seem to not purge the USB port. If you try to reconnect it can't reconnect the camera. To reset I found I needed to close the lid on the computer to put it in hibernate mode and than open again....which seems to purge the port connection. I tried the same time and delay with Maxim DL and it works fine....no issues with pausing and starting again. No freezes, hangs, etc. I can simply just use Maxim DL but thought you would want to know there seems to be an issue in the CCDops software with the STi and fast exposures and short delays between images.