I’m new to the CQ-18T as well, and also upgrading from Yamaha (MG10XU)
Just got mine A&H unit yesterday (literally) and I’ve run into a few glitches myself w/ initial network connections.
As for your (2) questions…
1. You can (actually, must) save “Shows” (w/ up to 100 scenes) and “Libraries” to a USB stick, which also facilitates backup / transfer functionality of sorts.
2. Yes, there are a few other FX options available natively in the unit itself. Click FX button > Click the top-right folder icon on any FX screen to access the FX list.
Looking at the screens, it SEEMS like new FX could be made available via firmware updates. Sure wish it supported VST plug-ins LOL !!!