I just upgraded to Designer Pro X 18 from 17, and once I activated 18, I uninstalled 17. Version 18 loads just fine, but when I try to install the content installer and Pan Studio, the installer complains that I "must first install Xara Designer Pro X". I've shut down and restarted DPX, checked "about", checked my list of registered products on the Magix site. My confirmation email shows my serial number and confirms that the Update Service for this has been extended to 6/17/2022. The product loads and is activated. It's just that the installer programs for the Content and Pan Studio don't recognize that DPX 18 is, in fact, installed.
I see that others have raised similar concerns. Please let us know how to get these working!