Innomen, Are you using your backup or one you downloaded?
You may be able to adjust the brightnes by loading the firmware into Firmware Modifier
HERE thet has a contrast adjustment then save and reload to your player. If the images are mirrored this can't be fixed the firmware is not the right one for your player. The only firmware I can direct you to are in the download section if someone with the same version reads your post they may upload it for you.