Cannot load tiled map in win8 release preview

cocos2d-x C++
#1

I’v installed VS2012 RC and win8 release preview.
The sample codes work fine,but i found the tiled map can not be loaded in my projects.

The code is as below:
CCTMXTileMap *map = CCTMXTiledMap::TiledMapWithTMXFile(“ios-test-zorder.tmx”);
addChild(map,0,kTagTileMap);

I have put the “iso-test.png” and “ios-test-zorder.tmx” in the Assets folder, but the map pointer always return NULL.
I also tried the TileMapTest in examples, and only four maps can be loaded, the others will report the same error as above.