Any RNS 510 Experts (West Mids area)

[RichUK]

Are there any RNS 510 experts on here? Basically my headunit got stuck on the welcome screen the other day so I tried to do a firmware update to fix it, and it went wrong. I think the firmware I tried to load (4020, I also tried 3810a but that just made things worse) was for later models, it got almost loaded then stopped and went to a fault screen, I've since managed to load the recovery firmware by a guy called Josi from the VWnavi forum, and it's working now but only very basic functions and no touch screen, also it won't switch off so I've had to pull the fuse.

The sticker on the top says 1TO 035 680 A HW: 104 SW:1000

I've searched everywhere for an older firmware version, such as 1100/1200/1300 but all links are dead.