Oh help - calibre-Opus-dust ?

[carpetmojo]

I'm slowly getting the hang of most of the Bookeen Opus I gave 'er indoors for Christmas - having solved one major boo-boo already....

I now have a little dust problem which I think might be down to me and the Opus, so please bear with me.
I hope I don't cause ire in the Mod's dept.....

I have downloaded books from Calibre to the device OK.
I then tried today with a couple test cases from a "major seller".
I d/loaded them to file on my PC and elsewhere, then "sent to device".

No "auto-convert ?" prompt came up, which usually does, but the library shows (green tick)/ says they are on the Opus, but they're not.
So I went back, pressed "convert ...s" then "sent to device".
One (the smallest) told me it had done so. Again, it wasn't there at all.
The second (a "complete works" jobbie) says it's on the device (it's not) but the "convert" job status just remained "stuck" on 47% !

Do I need to do something specific to the Opus within Calibre to sort this, or do I need to ask in "the other place"?

Or am I -as usual- doing something really dumb, particularly when obtaining supplies from "this source" ?