We don't have any plans right now to add nki support natively. There is now scripting support
for the Gig and SFZ engine of LinuxSampler, which is leaned on NI's KSP script language, hower that's pretty much it. We once had a NKI tool
that allowed you extract and repack the XML portion from/to nki files, but NI reacted quickly and changed the file format. So since v5 it does not work anymore and its pointless to fight against windmills.
Even if there was no such thing as encryption, obscured file format changes, etc. we probably still would have no plans for adding native support for nki. Because from the experience we made from adding suport for the Gigasampler/GigaStudio format, it wastes so much time to implement an accurate resembling of the behavior and sound of an existing proprietary format and sound engine. We are talking about development factor of 5 ... 10 compared to implementing either an open format or own/custom format. So that development time is better spent on SFZ standard features and our own custom features.