Glo Organize books from SD card

I spent weeks on making a perfect tree-structure for about 2500 books. it was selected by layers of category, writers, series, etc... very nice and very easy to scoop through 2500 books, to get the one you want. Now I inserted my SD card with this format into the Kobo Glo, and it became just one long list, sortable by title, or author. no structure, nothing. total crap, to be honest.

is there a trick, or do I really have to sort everything out again in those shelves, and is it possible to have a tree structure in the shelves?

like this

shelve 1 = Horrorbooks
shelve 1, layer 1= ---------- map with Stephen king
shelve 1, layer 2 = -------------------------Stephen king - blood series
shelve 1, layer 1=----------- map with Clive Barker

Just the normal, easy-view stuff....

what's the use of having a possible 30.000 books on this device if you cant sort em out properly in categories and undercategories. At least allow to sort by Genre.
might be I missed something but so far I really dont like the kobo desktop app. so simple. if I wanted Simple, i would have bought an apple Device.

some tips would be very appreciated!

thanks, Ripper