Currently, from 10.10, the system no longer permits unsigned kexts to run. The only public way to circumvent this 'security' measure at the moment is to disable all kext signing checks, which is a less than delightful solution.
The other way is limited to those with Apple development signing capabilities, which involves signing the kexts with your own certificates which will then enable them to run under Yosemite. This second choice has some manteinance costs, that would mean that SVS couldn't be free anymore.
The current release version seems to work anyway, so this affects only future releases
I just got a new Mac Pro 2015, with 1010.1 installed. We did updates when we got it. SVS installed fine but when I modified the kext file for custom resolutions I receive a "Driver Not Loaded" error and the menu icon is red. I did the same process on two macbook pros 2011 with Mountain Lion with no problems. Could it be because of what you're saying here? Thanks.
Definitely. I assume you can solve this by following this guide:
Please read carefully all the guide and be aware of the possible issue with NVRAM/PRAM resetting you may face, but apart from that everything should work just fine
I confirm this solution works, although the lower frame rate issue persists on Yosemite. Given that this program is designed to run on Macs, it would be great to have the typical Mac resolutions embedded in it so that we don't have to edit the kext file at all. I use Syphon along with screen sharing in order to use my older computers as a second monitor. This gives a much better font rendering than streaming solutions like AirServer. I have two iMacs and a MacBookAir, and they run respectively at 1680x1050, 1920x1080 and 1440x900. None of these resolutions is covered by default in the kext file! On the other hand, resolutions that have never existed on a Mac like 320x240 are among the supported resolutions.
Ok, I am happy this works for you. As for your request about the default resolutions I'll track it in a different issue (but I am not sure when I'll found time to implement it, sorry..).