Seems not working, first popout requiring libgcc_s_dw2-1.dll then libstdc++-6.dll, I downloaded and placed both files into plugin dir, but still not able to open pjg files compressed by packJPG 2.5a
I use with Xnview 1.99.1 on windows XP SP3.
I hope this is still on the todo list too.
I used to use AMP Tile Viewer, lately I found Imagine has this feature.
It would be a great benefit if XnView support this feature.