Fixed the headache by reinstalling the whole damn thing from a scratch! @Th3Z0ne Live boot showed that the controls work, so I figured reinstalling would work! And it did! Except I haven't the heart to use 'prelink' anymore... I'm pretty sure prelinking screwed shit up!
Anyone here using prelink? I know Fedora enables prelink out of the box, and there's been arguments over whether it is worth doing so?
@CaptainChaos Just FYI, while I was reinstalling it occured to me to check your theory. So, after I reinstalled Mint 18.1, which comes with kernel 4.4.x, I checked that Killer 1535 was "unavailable". So, then I updated the highest version of Kernel visible from Mint's update manager, which is 184.108.40.206. Reboot, and guess what? Killer 1535 was still unavailable!
I had to get the firmwire on my own, then modprob to activate the wireless card! But at least it works!!! The lesson that was hard learned, however, is that taking the risk of doing a kernel update from the version the distro comes with to the latest edition of kernel it allows access to, in this respect, does nothing to solve the problem.