kW X-port version 1.4.4 is now available for download. This version brings back the missing scripting interface, and also fixes the bug where you had to open a file twice in a row to restore the settings saved with the file.
Download kW X-port 1.4.4 for 32-bit 3ds Max or kW X-port 1.4.4 for 64-bit 3ds Max.
There is a known bug in 3ds Max, where a skinned mesh will not be exported correctly if the modifier stack has more than two items in it. To export correctly, the stack needs to contain exactly one Editable Mesh modifier, and on Skin (or Physique) modifier right on top of that. While it would be possible to work around this bug, it would take way too much time, so I'm waiting for a fix from Autodesk. In the meanwhile, make sure to properly collapse the stack before exporting.
The support for 3ds Max 2010 and 64-bit causes a memory leak on 3ds Max 2010. This is not something I can do anything about, but something which is a bug in 3ds Max 2010. Autodesk knows about the bug, but does not appear very keen on fixing it anytime soon. If you have contacts there, please tell them to fix the "IGame Release crash in Max 2010."