_runA2CO_beta not launching

[Tomaera 0]

Hi there.

I've done the following in order to install dayZ for a steam copy of ARMA 2: CO manually.

- Got the latest 1.7.2.5 version and placed the files in the arma 2: OA >@dayz > addons directory

- Got the latest CO beta patch and installed

- edited the '_runA2CO_beta' cmd so that the line is "-mod=%_ARMA2PATH%;EXPANSION;ca@dayz"

- Verified the integrity of the game cache files through steam

- reinstalled battleye

However, despite my best efforts, whenever I go to play the game, launching the beta version with _runA2CO_beta just results in the command screen flashing then ending itself. No game is launched. No error is given. Nothing.

Have I done everything correctly? I've followed the instructionals word for word, even tried using Dwardens 'simple installer' from: http://forums.steampowered.com/forums/showthread.php?p=30959197

I've also tried using 6launcher/updater but the version of DayZ it installs is 1.7.2.4 and doesn't seem to agree with my (completely reformatted as of yesterday) computer, giving me the infinite loading screen.

I've tried launch combined ops with the -dayZ shortcut option in steam and I get the message of "You cannot play/edit this mission; it is dependent on downloadable content that has been deleted.Chenaraus" I have redownloaded the mod files with no success.

Help?!?!