Error building OSX only.

I'm trying to make an editor script that will build several versions and then place them in corresponding folders, it works fine for the WIN/NIX builds but always fails for OSX, building on a Windows Machine(win 8).

     [MenuItem("Build ALL")]
     public static void Build_All()
     {
         string deployPath = ppUtility.pgBuildAllDeployPath;
         
         PlayerSettings.productName = "pw";
         string appPath = deployPath + "builds" + "/" + "/" + "dist" + "/" + "pw" + "/" + "win" + "/" + "32" + "/" + "pw32.exe";
         BuildPipeline.BuildPlayer(new string[] { "Assets/pp/pw/main.unity" }, appPath, BuildTarget.StandaloneWindows, BuildOptions.None);
         Debug.Log("pw (WIN32) build " + DateTime.Now.ToString("dd MMM HH:mm:ss"));
 PlayerSettings.productName = "pw";    
         string appPath5 = deployPath + "builds" + "/" + "/" + "dist" + "/" + "pw" + "/" + "nix" + "/" + "32" + "/" + "pw.x86";    
         BuildPipeline.BuildPlayer(new string[] { "Assets/pp/pw/main.unity" }, appPath5, BuildTarget.StandaloneLinux, BuildOptions.None);
         Debug.Log("pw (NIX32) build " + DateTime.Now.ToString("dd MMM HH:mm:ss"));
 PlayerSettings.productName = "pw";
         string appPath2 = deployPath + "builds" + "/" + "/" + "dist" + "/" + "pw" + "/" + "mac" + "/" + "32" + "/" + "pw32.app" + "/";        
         BuildPipeline.BuildPlayer(new string[] { "Assets/pp/pw/main.unity" }, appPath2, BuildTarget.StandaloneOSXIntel, BuildOptions.None);
         Debug.Log("pw (MAC32) build " + DateTime.Now.ToString("dd MMM HH:mm:ss"));

deployPath just being a reference to "/../../" to go up several folders.

This will build the win and linux versions fine and put them in the appropriate folder. OSX will always result in.

 Error building Player: IOException: Failed to Move File / Directory from 'Temp/StagingArea/UnityPlayer.app' to 'C:/unitypp/pw/Assets/../../pw/mac/32/pw.app'.

I tried tons of things, launching with admin, restarting unity, computer, putting extra /s or removing them, changing them to \, anything I could think of.

The issue, as I've discovered, is that ONLY when building the OSX version, Unity cannot create new folders automatically(which works fine with win/nix). If I create the target folder before building, it works fine.

Any ideas why this is this is an issue only with building the OSX version? and thoughts on ways to over-come it?