Quiz with customisable pdf certificate

[ Moved to the Fixing WordPress sub-forum. ]

Hi everyone, I am looking for a plugin quiz that produces a pdf certificate on completion. I would love to be able to upload my own custom background image. I thought quiz and survey master was the ideal solution but I am having problems getting it to work with any sort of image in the certificate.. Support is very quiet and I am not getting any help. I need something similar, easy for a beginner to use and has a good certificate customiser. Thanks in advance.