Touch Problems with ADE books on Kobo Touch

[vmsda]

I am enjoying my Kobo Touch, but there is always a but ...

I bought a uSD card and followed the relevant Kobo official instructions in order to store on the card some Adobe DRM EPUB books I had bought from Kobobooks.

I then inserted the uSD onto the Touch and noticed two problems:
1. On most of the books converted by Adobe Digital Editions (ADE), the cover image was missing (not terribly important).
2. (Important) On all converted books, the Table of Contents is grayed out and thus inaccessible; it can only be viewed as a normal text page and obviously not possible to jump to any section/chapter directly from it.

Since the problems could be blamed on the Touch or on ADE, I decided to experiment by stretching my inherent technical limitations, and:
A. Removed the uSD card from the Touch
B. Went back to ADE and loaded one of the converted ebooks back to the Touch (this time, of course, it went into Touch's main storage.
C. Ejected and restarted the Touch, opened the book and, lo and behold, the cover was still not there but, most important, the TOC does work fine.

So I have concluded, I hope rightly, that the blame rests with the Touch software, which handles the same input differently, depending on where it is stored.

For those of us who plan on buying, or need to buy, or have bought uSD cards, this is a serious issue. Does anyone know if a bug has been reported? Is there any workaround to the problem?

Any help would be greatly appreciated.

Vasco