For convenience when creating and testing a DiveTab module, there is an option in the Workbench Tools menu to launch the client. After installing DiveTab, use Workbench Tools > Preferences to specify the Path for the "DiveTab-PC executable". To launch DiveTab from Workbench, click Tools > Launch DiveTab-PC.
A properly configured DiveTab connection that is open in Workbench allows Tools > Launch DiveTab-PC to pass the DiveTab Project URL and authentication credentials to DiveTab-PC.
See also Launching DiveTab-PC from your Windows Machine.