I'm trying to build an addon that has multiple sub-modules located in the same folder as the
__init__.py that pulls everything together. It's exactly the same set-up that's used by the delivered Add > Curve > Extra Objects addon.
I keep my development files in a Dropbox folder. Unfortunately, when stored there, Blender can't load the submodules when it encounters
from . import XXX.
Trying to diagnose the problem, I made a complete copy of the delivered add_curve_extra_objects addon to the same Dropbox folder where my addon resides. When run from there, even the Curve Extra Objects fails.
I tried adding the Dropbox development folder to the Blender preferences scripts folder, but it still fails.
The screen shot below shows me trying to execute the Add > Curve > Extra Objects from a VSCode session and the errors it produces.
How can I develop addons in a custom location and have Blender still be able to load the submodules?