In your start up script use the Show/Hide Toolbars [Lock;Hide] script step to suppress the toolbar.
Have you tried enabling the kiosk mode from within the FileMaker Pro Advanced Developer Utilities? It turns your database into a fullscreen app for all accounts that don't have the [full access] privileges. As this also affects the solution when opened in FileMaker Pro you may take into consideration to provide a special interface file only for FileMaker Go clients.I can recommend this article about Integrating Kiosk Mode into your Solution. You may want to test this with a copy of your database first, because disabling the kiosk mode requires a few more steps.Nils