Next time you run BioDownloader, select a user account with the session of interest:
The Main Window of BioDownloader will be opened with the last configuration of such session: task list, graphical user interface preferences and settings, recent folders, recently opened tasks, recently appended task lists and etc.:
All tasks in the task list will be in the Not launched state. So, you may launch any of those tasks separately or launch all of them at once, List → Launch all not started or List → Restart all:
All tasks in the task list will be running: