Missing book covers for books downloaded thru Companion's Dropbox feature

Hey team:

Device: 2015 Kindle Fire tablet

I *love* the idea of calibre companion working with dropbox. Only problem is, as per https://www.mobileread.com/forums/sh...d.php?t=290192 ;; I had to move the companion data to main sd card (not my external sd card) to avoid calibre database corruption notices.

Because of limited storage space on the fire, I use the external sd card for my calibre library as well.

So... once I do this I can download books just fine, but the covers are no longer present in moon reader pro.

Anything I can do to resolve this? I kinda like the cover view.

Thanks!
arooni