I don't know what sidewalk setting would be best for you to avoid the curling issue - I'd experiment with the settings. I think if you turned OFF the sidewalk perforation, that might give you a greater chance of avoiding the curling that has been plaguing you, but it would likely make for more post-processing to remove the sidewalk.

You can certainly adjust the heights of individual nozzles - and you should if they are not aligned. Check the user manual or contact Cubify support for instructions. I can't walk you through it via this forum, but I know it can be done because I've had to tweak my printers settings.