This is still not fixed so anyone wanting to install QDKPViewer here is the fix. The file in the downloads section still hasn't been fixed and took a while for me to find a fix in the forums as it's embedded on page 2 of a post. Here is the fix displayed more prominently for passersby.

Install Errors
The install definition file for QDKPViewer did not contain a correct installation class

CHANGE
/inc/install.def.php line 27 from:
class QDKPViewer
to:
class QDKPViewerInstall

Installation should now work.

this is fixed

if you check download section there are diferent versions available to download

try versionv2.0.0.1b instead of v2.0.0.0b

to avoid further confusion i removed the old versions from download sections

if for any reason you need a old version feel free to contact me