Hi Rafal and nosmirck,
I wrote the post on denvycom (http://denvycom.com/blog/setting-up-cocos2d-for-blackberry-10-development/) about setting up Cocos2dx for Blackberry. Basically, I imagine the WebPInitDecoder error is as a result of a missing or unreferenced code file were it has been defined. Like I mentioned in the post, commenting out these files made the BBTemplateProject build successfully and run on my BBz10. Thus far, I have had no trouble using the BBTemplateProject (with the commented files) as a base for my preliminary projects .
Did commenting the files out solve your compile errors ?