I'm currently using Flash Builder 4.0 on a project that handles a large amount of images at once. Even after upgrading to Air 3.0 recently, the program will start to act weird and eventually hang after reaching about 1.3 GB of memory usage. I think I've pinpointed it down to when creating BitmapData during this high memory usage. When the program stops responding, I don't get any errors and the console only shows [SWF Unloaded]. This problem is only happening on Windows. Right now when I export an air installer, even on Windows 7 x64, my program only runs as a 32bit application. If I upgrade to Flash Builder 4.6 will I be able to export an air file that will run as a 64bit application? Or should FB 4.0 be able to export a 64bit installer and I just have something setup incorrectly?
AIR applications are 32 bit, there is no native 64 bit support at this time. I'd recommend looking into aggressively reducing your memory footprint. If 64bit support is important to you, please take a moment and vote for the following feature requests: