Place separate links in individual parts of a UI image, to simulate full interactivity.
Importing images of high fidelity UI designs is a great way to quickly mock-up a HUD or menu screen. But these can't be fully interactive. A single image can only link to a single scene.
Use small cubes, stretched and skewed, to represent interactivity for separate parts of a UI image. Then set the cube colours to "none" to make them invisible.
See this video for an example.