Ok, the command script included with steam sucessfully launched Arma2 with Operation Arrowhead.
Do I run the command script every time, or do I set up a shortcut with the parameters posted earlier in the thread?
EDIT:
Yes.
The shortcut parameters don't work either. The Combined Arms option in steam launches a dosbox that creates a bunch of messages then closes before it's readable. No game launch.
The command script no longer launches anything. I edited the command script as discussed on page 11 and a couple of other pages. no luck. At best I get an error complaining about steam protections.
Edit:
I reinstalled both Arma2 and OA. Began working again. It seems that after verifying the file cache, you have to run both games again one time before using the command script to set the registry?