Hi. We looking into this and hope to advise in depth thereon no long.
EDIT: While it is possible to run a custom ROM on the model, it does not seem like any has ported one specially for the model and trying those that are not proven may be hurt-some. If you are willing, I would suggest you take a ROM backup as per the tutorial here (do let us know if successful with the backup) > and then proceed to tinkering with CM12 porting as per the tutorial here. As for the VF1296 file from sourceforge, there is a good chance that it is a manufacturer stock ROM similar to yours though we probably will never know until it is downloaded > extracted and tried. Backup first though.