it would appear that there are even newer SBIG drivers/firmware announced yesterday. this line in the announcment worries me a little bit:
STT, STXL, and STX models get improved shutter handling. Autoguider shutters and main camera shutters are now fully decoupled. This reduces unnecessary shutter operation. (Your control software may require an update for this feature to work.)
given that the STT needs the SGP API Guider for the OAG to work, i wonder if @Jared can comment on this. @Andy might be interested as well. to be honest i'm not sure what problem they were trying to solve: currently if the main shutter is closed, then the guide shutter opens and closes with each exposure. if the main shutter is open, the guide shutter stays open (and presumably the guide chip has an electronic shutter). with this update, perhaps they are allowing you to open the guide shutter and leave it open during guide-only exposures, which would eliminate the clickity-clack we get right now. in that case the shutter is only for darks, i guess. at any rate it seems to me this update could break one or both of PhD2 or the API Guider.