I've been doing a similar thing with various cruising guides
. I use a PDF file for the cruising guide so I can open the file to a particular page number. The PDF's open in the default web browser.
I would also like to see a place where these files could be placed so that it is not necessary to name a full pathname. For simplicity, I have just placed them in the "C:\" directory. It would be nice if we had a dedicated folder we could copy these files so no path would need to be specified and would be usable on Android and other devices.
Perhaps we could have a folder named Layers/Data or something like that. OpenCPN
updates would need to protect those files between updates so they never needed to be reinstalled.
Suggest you add this feature requests and post an entry in Flyspray requests. I'll vote for it!