I'll admit, that's the biggest downside to the QQ-S. There's not really any support. I got this for around $270 on Prime day so I'm not complaining too much.

I did have luck with the VERY small FLSUN subreddit. I posted about my stretched belts and one of the folks there gave me extremely detailed instructions for how to replace the belts. It was great.

As for Octoprint, it's really the same method on this printer as any other. You just specify all the necessary settings once it's all set up.

I used these instructions to set up my OctoPi on both my printers and it was pretty easy, even for someone who has never worked with a Raspberry Pi before.