Hi Amber,
Can you first check that you have auto-update mode enabled before you click the ‘render’ button? This should be the default option, but if it has somehow been changed, that would explain the behaviour you’re seeing.
You can select auto-update mode by clicking the ‘cog’ button in the Shaderlight toolbar and then choosing ‘Auto’ from the ‘Update’ dropdown menu.
Zooming the render is achieved by operating your mouse / trackpad’s scroll-wheel function. On macOS, you also need to hold the command key to activate the zoom control. Once you are zoomed in enough that the image doesn’t fit within the render window, you should be able to pan by clicking and dragging within the render window. On macOS you can also pan by using your trackpad’s scrolling feature.
Regards,
Shaderlight support