I've changed the max rows from 2 to 3 and it sticks with 2.  I've deleted the backpack items from the Data>Backpacks folder and reloaded the plugin with the new config and it still shows only 2.  I've disconnected, unloaded the plugin, deleted the data from Data>Backpacks, checked that the config says 3 rows, reloaded the plugin, and then connected... still only 2 rows.  What gives?

Sounds like you have the permission backpacks.use.2 granted. Permissions overwrite the default size.

Ahh.  Nailed it.  Thx.