What project is it for? Is it for a commercial game? Something else?
I am registered dev and I've been in touch with Nvidia devs since Steam on Linux went to live testing phase. So I do get respond via e-mail. I don't expect driver devs to hang out on the forums. Forums are for discussions between other devs, and for someone like Jim to notice critical issue and communicate it to the driver engineers. Perhaps your issue was fixed in the driver update (like mine was), and they expected you to update driver. It doesn't seem you were persistent enough on the forums, thus it might have been assumed that driver update fixed the issue ?