Hi Dave,
Here is a link to the 3.12.0 Cumulative Installer that I have:
http://adventure-unlimited.org/misc/PF3 ... 210829.zip
The process I followed to reinstall this was to de-register the current version, install my base install (from Aerosoft, I think), re-register and update with this. I have done this twice (a couple of months ago and very recently) and both times it has put the gauge back to proper working.
The tgs.gau I am using is dated 2/1/09.
TGS_Display.exe appears to work correctly, but I only have one screen. I do run FS in windowed mode using about 90% of the screen but there is insufficient space to display TGS_Display.exe big enough for my eyesight. I did try a third-party utility to make it display "always on top" but that stopped it working. If it had a feature that did keep it on top of the FS window that might be a solution for me.
Not sure what else I can tell you at this stage, but ask away. I am away early in the morning for more eye attention but will reply when I can.
Hope you had a good Easter break and anniversary.
John