You can browse the network manually by right-clicking on a closed drive list and selecting Browse network , or enter a network drive directly.
Backer remembers network drives for future access.
In the source, I want to select individual file types for each directory. There is no technical reason, we just didn't want to clutter the user interface. Create an individual profile for each combination of directory and file type and put them together in a batch file. I want to backup from more than 1 drive in one run. The limit of 1 drive in source and destination has the technical reason that files must be related unambiguously in both directions.