Hi Andy,
I am sorry that your camera needs fixing. I am sure QSI will do their best to find an effective solution quickly.
I have also been using Nebulosity for quite some time, but did not like that it does not have an option for a gradual warming up of the CCD (as well as gradual cooling). Therefore quite recently I swapped Nebulosity for Sequence Generator Pro. To avoid rapid temperature changes I set a gradual cooling and also warming up of the sensor at the end of imaging session. Also, since SGP has much more options and automation (including autofocus and plate solving - great for multi-night imaging sessions of the same target), I have not not looked back at Nebulosity. I am sure that Nebulosity is fine, but I like to look after my equipment as well as I possibly can so that it hopefully will last longer
Regards
Slawomir