fix tips for a busted retractable cargo cover for my loyale wagon?

i bought a used retractable cargo cover for the trunk area of my Loyale wagon last here on the USMB and recently it stopped retracting and i can't figure out how to get it working again. i didn't want to take it apart first, in fear i might break it trying before relying on the past experience of other USMB members. 

tips? 

or if you have another one i can buy, i'm interested, any color, EA82 cargo covers are pretty universal?

thanks, 

Glen