Wow, you do seem to have had a few problems, with regards not providing support, Obviously I don't know what they said, but they do still support RedSDK, and indeed in 2018 it is a 'paid for' plug-in, or at least it will be when they get round to marketing it.
Some things, like the palettes thing, do sound like a graphic card issue, but I'd only expect it to really be a problem in RedSDK mode, assuming RedSDK is using you graphics card and not any motherboard graphics, (options menu - native draw - show video system information).
I have not got 2018, but in theory, without RedSDK TC should be stable, that said I've used RedSDK in v2015 v2016 and v2017, and have not found it to be too unstable, though our systems are completely different, (mine is a windows 10 desktop, old gtx 660 graphics card).
Hope 2018 performs much better for you.