Problem:
The user has an my-account page on a menu. He wants it to switch to login for guest users.
Solution:
The Account page is being added to a menu, specifically to the Main menu. Check this screenshot http://prntscr.com/1tonx8y
Please note that Toolset has no effects on menus. Even if you define rules in Toolset Access, that would not affect WordPress menus. Basically, if you want to customize a WordPress menu for logged-in/logged-out users, you will need a custom code solution or a 3rd party plugin. Toolset plugins have no effects on them.
An example of a plugin to customize WordPress menus: https://wordpress.org/plugins/if-menu/
