When configuring subnet profiles, you can double-click a field in the Subnets table to edit an individual entry, or take advantage of right-click commands to add, delete, and copy rows in the table. You can also right-click a range of rows and use the Fill Increment or Fill Decrement commands to automatically enter values for various fields.
Please refer to the Avalanche online help that is accessed by hitting the F1 key in the Avalanche Commander GUI and then searching on "Subnets Tab Right-Click Commands".