Really all universal booklink platforms are a pain in the ass. Either they cost a shitton of money, do only support a specific subset of online stores, are totally US centric or build links to stores in an old URL scheme the store does not support any more. *sigh*
I know how this should be to be a good store in just do not have time or skills to do it *sigh*
Fellow #authors, which UBL platform do you use?