As of WorkWithPlus for Web 15, in the main node in the panels within the instance of a transaction, you will be able to find the Permission Prefix property, where you will be able to determine if at the moment of generating the permissions, these web panels will have their own Permission Prefix or if it will take the same value of the parent object.

If it has <default> it will take the value that is defined in the template within WorkWithPlus Settings > Transaction Template (main). If the value is <Same as Parent Object> it will take the prefix permission of the transaction, so by having this permission you will be able to use this screen without having to assign another specific permission to access the web panel.