Will do as soon as I find some time. Basically I preview my HDR alignment by piping the HDR as a bitmap node into the environment slot (max key 8) and adjusting the U or V offset until it is located/rotated nicely. When I then put that offsets inside the VRayHDRI Map, I get a different result. (Bitmap setting: Environment - Spherical, VRayHDRI setting: Spherical) maybe it has to do something with degrees and radians? I dunno at the moment.
The max API/architecure must be pretty horrible I imagine. So much stuff that you can do already in maya even though you had vray far longer for 3ds max 