first, do you have more then one wow account? If so, with upload all accounts checked, and you have not yet logged on to every account with character and or guild profiler enabled, then UU wont find the .lua in that account, and it will throw a fit.
As you are on windows 7, where is your wow data saved? is it in the wow folder under wtf? or is it in the %user%/%appdata% folder? if your wow is installed to ether program files or program files (x86) then chances are they are in the appdata folder, and the new UU version may have defaulted to the wow folder,
is the update.php file for your roster there, accessable, and executable?
P4: mscorlib
P5: 2.0.0.0
P6: 4a27471d
P7: 349e
P8: e1
P9: System.IO.FileNotFoundException
leads me to also question if your .net install is possibly corrupt, out of date, or possibly windows 7 has not granted UU administrator status.
My UU was able to send data to your roster with no crash, it is based off of r73 from the svn
just running out the basics that come to mind when i read your problem, and hope it helps