Is 2018 not backwards compatible? none of our 2017 cadworx piping models are usable now that we've upgraded to 2018. components appear to be broken up or "ungrouped" and are uneditable even when using the same specs

Forwards compatibility is usually not a problem, so its strange you mention your models are unusable. I have seen the issue where the solids seperate from the component centrelines. This is usually fixed with a convertsolid.

What exactly do you mean by uneditable ?