For my specific reason I needed to send a render of a selected object. I've been trying unsuccessfully to send a job to render over the network using the "setRenderType #selected" active to render a selected item only.
(in combination with VRay's "renderers.current.imageSampler_renderMask_type = 2")
Problem is - once it gets to the network, my object is no longer selected.
So I delved into the Pre-Render script. However, even though I managed to create a small single-line script that selects my object and set it to run before the render (pre-render) - Max would constantly ignore it: