CONNECT X5 thumbnails not showing X3 and X5 *.CDR files.

Recently had problematic re-install of both X3 and X5. Finally succeeded in sequential numeric order (i.e. first X3 and then X5). However now, CONNECT X5 no longer displays CDR vector file thumbnails.  Currently CDRs are associated with X3. Is that the possible cause? What else might be contributing to this problem?

Thanks for any and all ideas!

Happy New Year!