Thanks for getting back to me so quickly!
Well, Mudbox 2015 gives an error on startup after placing your script in the /plugins directory, so maybe it needs recompiled for 2015?
Mudbox::LoadPlugins: Failed to load the following plugin(s):
C:/Program Files/Autodesk/Mudbox 2015/plugins/ApplinkBeta.mp
This is with the attachment that you posted, and also the installer file from the main Applinks page: same result.
Transferring polygons (on layers) between the two apps is all I personally need for conceptual 3d work, though I suppose preserving mudbox/3dc paint layers and UV channels would be desired if I was doing more painting: your plugin may already do this flawlessly, but I have used it for quick geometry transfers/retopology between the two programs. UV work in 3d-coat makes perfect sense after quick retopology. The option to paint in either app can be a personal choice so long as data is not lost in the transfer. My feature requests are more on the geometry/UV side of things, as I would use Mudbox to paint with.
Many thanks for all you've done with it! Let me know if I can help test or anything.