Tabtastic allows you to divide rooms into ‘buildings’ (even if those rooms are virtual), which allows you to easily set one link for multiple rooms if they are in the same meeting. Discord and Google Meet based setups do not require buildings, however having at least 1 building is required for Zoom Allocations to work.
To create a building, you need to create a Room Category on your tab with all of the rooms you want to be contained within that building. Once you have created your categories, you should navigate to the Allocation tab of the Tournament Manager, and select your room category from the drop down. You can optionally add a comment to help you identify which category is which. This room category will now be treated as a building when running a draw. Once a category has been added, you can update it on the tab without needing to make any changes in Tabtastic.