Furohman

I suppose this won't work since my base ArmA 2 is retail and OA is Steam. The mods from base ArmA 2 transfer over fine so it recognises the install... This registry thing all seems like a bit of a messy way to do things. And ArmA 2 isn't even one of the games you can activate on Steam from retail so if it doesn't work I'm completely out.

I own ArmA 2 retail and Operation Arrowhead through Steam. OA recognises my ArmA 2 install and the mods installed for the original game work with the expansion as normal... But when I go to launch Combined Operations through the option on Steam, this command window briefly pops up and goes through about 6 or 7 similar errors, I could only catch a screenshot of the first couple. What exactly does this mean? Is there a way to fix it?

I heard about the Alt + E main menu shortcut to the barely usable 3D editor and tried it. I wish I hadn't. Now when I enter the normal editor, the option for placing empty vehicles has disappeared from the 'Side' list. Is there any way to fix this?

This isn't a problem with the DVD itself if the file it hangs and errors on is different each time like it is for me. It's a problem with a number of DVD drives which just aren't fast enough to write the files effectively. I would try the copy all files to hard drive and install from there, but my hard drive is tiny and I wouldn't like to waste that much space unless I know it works. Update: It worked perfectly, I'd recommend at least trying it. If all the file sizes match the ones on the disk and you still get problems with them then it's more likely it actually is a physical issue with the DVD itself.