1. Select the tiles you want and go to the tools pull-down menu and click 'exit'.
2. Scroll your screen over and then back - voila, green exit-grid.
To make the grid pop up at the appropriate time use a trigger. Set the action to 'Toggle Exit Grid' and the condition to whatever.
Exit Grid SwitchEdit
To make an exit grid switch follow this
2. Click on entity and find the switch you want to use. Give it a 'Tag Name', 'exit' for example.
3. Create a new trigger with a new condition.
Object Script State of 'exit'
4. Create a new action.
Turn Exit Grids 'On'