You've tried it all then... Except - If the game seems to load, but seems to hang at the 3D stuff, in spite of it being a Steam version, try the DirectX9c install again. "Updates" from Microsoft involve removing software they deem "legacy". DirextX9c is such, and the SH series is "Super-Legacy"
If it doesn't get that far, and hangs at the start, it might be a Steam / Valve versus Microsoft thang, and you may have to wait for a Steam app update - DRM. Try loading Steam itself and log-in. Like you say tho - you might have to wait on an MS response...