I'm using XnViewMP Version 0.68 (May 19 2014) on Windows 7 x64 to resize my raw image files and convert them to JPGs but it's not working as expected. Here are some images of the configuration used and general information.
Here's the original image file.
Original file (7z)
When I resize JPG files all works as expected.
Let me know if you need more info.
Cheers!