On the first image of the import window. I'm not able to reproduce that, the dates I'm seeing on my own system are correct; all thumbnails show the date taken. That applies to both import from camera and import from USB or Card Reader. I've no idea why yours are displaying 31/12/1979... interesting date though, may be of some relevance.

Regarding the incorrect sorting shown on image 3 and 4. It looks as if digikam is sorting 'By Name' (that is, file name). Probably worth checking the setting of View => Sort Images. I do recall a while back there was a bug whereby the sort setting wasn't being retained, but I'm sure that was fixed. In 'digikamrc' ( located at: ~/.kde4/share/config/ ) 'Image Sort Order' should be '=2' for 'Sort By Date'.

All my problems are solved after having updated Digikam to version 4.0.0.

Pierre