I try to give some light on it (maybe wrong or missing something
)
You dont need to edit a manifest-file by hand (outside b4a) at all.
b4a is, while compiling, generating a new one each time. Some parts of the new manifest file comes from the region (app name, version)
some comes out of the content of the ide manifest editor.
I think a general rule can be; all changes to the manifest will be put in the manifesteditor in the ide. You just need/use this editor. Nothing else