Hi Andy,
yes, on "non-mobile" Platforms there's a way to "manually" copy your settings over to another PC.
I mentioned the paths here:
https://sites.google.com/view/narrowboat-simulator/downloadsExample: If your log on name is "Andy" then the path could be this one: (or similar)
C:\Users\Andy\AppData\Roaming\Godot\app_userdata\Narrowboat Simulator
If you use the Windows Explorer and you don't find the path, it could be hidden and you'd have to either enable the view of hidden/system files/folders in the Explorer options - or - use command line - or - another file manager.
The file you are searching for is "save_game.dat".
(save_game.bak can be ignored)
Ideally, you start the game once on the new computer and close it again, this creates the subdirectory on the new computer. Then replace the file save_game.dat with the file of your old PC.
This should also work when moving from Windows to Linux or vice versa. (linux just uses a different path)
If someone wonders whether that also works on mobile devices: Android blocks access to the save_game.dat unless you use a rooted device. (There might be other, very complicated ways to retrieve the file from unrooted android devices using backup tools /adb.)
Hope it helps,
Michael Donning