I uninstalled the 32 bit version and installed the 64 bit version. The mouse now works in full screen mode, but the meter is still unplayable. JackDunno posted this in another thread:
"If the problem started with an update of Firefox the solution may on
some systems (especially 32bit) be found in the configuration of
Firefox.
The fix:
1) type as adress in a new window: about:config
2) Don't be scared. Changes here can really do damage to Firefox. Click on yes you are aware of that fact.
3) search for the entry: dom.ipc.plugins.asyncdrawing.enabled
4) click to change from true to false
5) close the config window
6) start wgt and enjoy"
This smoothed out my meter but there was considerable lag 9 out of 10 shots. Still unplayable. I'll just change browsers or roll back to a previous version. Fingers crossed. Thanks for the reply phred952.