I’ve never done anything special to load VBA in studio. When designing a screen, just do an alt-F11 to toggle to VBA. It you want to manipulate objects on the screen, you will have to expose them from the studio design window to VBA using the property window. If you want to debug in run time, there is an option on the client configuration to check, and the VBA window opens separately. You can run and design code in the runtime independently, but you can’t save it there.