Models are not meant to be overridden as they deal with data.
However the plugin you mention seems to work with K2, so you can always try it. I would recommend that you first try it on a new Joomla site with K2 on it (only). And make sure error reporting is switched to maximum so you don't get these blank pages if actual errors occur.
Fotis / JoomlaWorks Support Team
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Please search the forum before posting a new topic :)