Document no longer visible when connected to internet

I imported a number of html-files to DEVONthink Pro (1.1.1 MacOSX 10.4.6), that i downloaded as a zip-file from the web, unpacked them on my desktop, imported them to DTP and then deleted the files from the Desktop. The Show Info… Command shows no URL and a Path to the Desktop that in reality no longer exists on the Desktop.
The documents display all right, if my computer is not connected to the internet - if an internet connection is active, these documents can be found via find/see also, the right word count displays, but the document view is EMPTY.

Any suggestions?

I tried to reproduce the issue but no luck so far. Could you send me an example file or the URL of the zip file? You might also try to delete the WebKit cache (~/Library/Caches/DEVONthink Pro).