Some nooby questions about changing detaills of the default theme

Since I modified the xmls for changing the design, the normal backdrops are not displayed any longer. 

How can I fix this problem?

So i’m assuming you’re using Linksheets for Folders and Normal Moviesheets for Files ?

There must be Breaking Bad s01e01_sheet.jpg in your tv/movie XML + Breaking Bad s01e01_sheet.jpg in the same Folder as your files.

And can I force the SMP not to display subitem: “NA” if there is no xml for the corresponding file?

You can’t unless you delete the label entirely in the Theme (see Tinwarbles post above)

Or maybe the Folder extension trick will work …  (and of course you will have to rename the Linksheets accordingly)

eg.

Breaking Bad.avi   ----- this is a Folder renamed with a media extension

Breaking Bad.xml  ----- this XML contains an show information (do not put this inside the folder)

This trick worked with my Live Hub(on old firmware)  to display Metadata for a folder … and you must use Linksheets for a backdrop

More info here: http://community.wd.com/t5/WD-TV-Live-Hub-Themes/Folder-Metadata-trick-for-FW2-04-13/td-p/254820

EDIT: Some cover or moviesheets are only displayed in folder view, while other are only displayed in TV-series-view?

(but most of them work in both views). Do you know the reason?

I can’t answer that without seeing how your files / folders are set up.

Carefully compare any differences between the working and non-working ones to see what the problem could be.