I usually get that one if I open compressed projects (one reason I never compress them)
when it comes to smart content and Daz studio saves, it usually needs fixing in Daz studio.
Resetting metadata or any other number of hoops to jump through.
my Smartcontent only started working yet again after coming and going when I installed Daz content manager DIM
even so I only use it when absolutely needed (no duf file, dsa only) otherwise I import .duf content to avoid freeze up errors
anything legacy (Poser format) I use the content browser.
I save a lot of presets in .duf while in studio for this reason, importing with figure selected brings up the dialogue “would you like to apply it to the selected figure?” whereas selecting Genesis and using smart content I invarably get “an error has occured!”.
I have shader presets like V4 male and M5 uv with V4 face, lip nostril uv for my facegen men etc and others esp mixing uv’s which you cannot do in Carrara.