There were two threads dealing with this issue. I believe you need an update on the WebcamCapture.exe file as this is aseparate file to WDisplay but is incorporated in the complete program download. However you can get it from here…
http://www.weather-display.com/downloadfiles/wdwebcamcapture.zip
Threads were…
http://discourse.weather-watch.com/p/184324
Both were in WD Bug Reports Board. You have to Search in there or do an advanced search selecting logical Boards only or the whole lot.
Hope this helps.