Add a condition to the buttons on the template. something like p_web.GSV('HideInsert') = 'Y'
In the embed that detects a user clicked something in the browse, grab the record and do your validation and update the SSV. You may need to refresh the browse to update the state of the buttons.
If the buttons are in the browse the approach is slightly different as you want to do the validation as each row loads.
HTH's
Kevin