Apologies if this has already been posted, I've search for as many phrases as I can think of in the forums ("Change Folder", "File Location", "Route Directory" etc), but couldn't find any mention:

Is there any way to change the default location for storing and opening Flight Plans with PC SD Plan?

Currently routes are stored in C:\Users\{MyUserName}\Documents\SkyDemon\Routes, but in order to have the routes available on all my various home/work PC/laptops/phones I'd like to be able to store them within my Google Drive so e.g. C:\Users\{MyUserName}\GoogleDrive\SkyDemon\Routes. I can store the files in that location and load them from there fine, but every time I click to open I have to navigate from C:\Users\{MyUserName}\Documents\SkyDemon\Routes to C:\Users\{MyUserName}\GoogleDrive\SkyDemon\Routes every time - even having opened a route from the new location, SD doesn't remember it for the next load let alone the next time it runs.

I've tried looking in the program preferences, for a config file on the disk and even in the registry, but no luck. I'm hoping someone can point out a way for me - perhaps there's a secret command line option that can be used when starting SD?

I don't see a problem with the wording in our documentation. The standard Save window that is shown allows you to save your routes anywhere you like. Only the default location is your SkyDemon Routes folder.