[tony_sologubov]

@xgarb, generally speaking the problem is caused by the fact that the $this->getCasestudy()->getProduct() construction does not return a product object. You need to find out why and it will be a key to how to fix the problem.

If you grep by 'fileObject' substring through X-Cart code, you will see that it is used for definition of POST variable where we should look for the actual file uploaded.