I recently had to reformat my ssd, and reinstall my apps.  When I updated to Kontakt Player 5.6.8 I also downloaded Native Access.  Then I registered VDL with NA, but when I "browse to the folder where I unzipped vdl", the location is in red, and I get this message, "library location invalid".  Eventually I got it to acknowledge the unzipped folder, but everything on the NA install page is greyed out.  Does anyone have a solution? 

I think the Native Access application has introduced a few elements of confusion to the mix when using third-party libraries, especially if they're older libs like VDL 2.5.

I realize this is a late reply and you've likely sorted this out by now, but in case it helps anyone else, we have a hackie workaround for anyone using Kontakt 5.6.8 (or greater) here:
https://www.tapspace.com/hesksupport/knowledgebase.php?article=129

My hunch is that this sort of thing will get simpler as Native Access evolves, but in the meantime, this workaround might be a safer bet, even if it's a bit inconvenient in the short-term.