I agree. It should be easily do-able. After all, most 3D game level editors start with a blank slate. You really don't need a reference at all, other than a grid with axis along the horizontal, crossing in the middle to indicate where world coordinate 0,0,0 is.
Which brings me to this request (which I am certain I've requested before) - Can we get a proper grid in GameGuru MAX? One that can be seen on screen (a toggle to turn on/off would be great) ... one that can be adjusted in size.
Also, can we get proper, adjustable snapping in GameGuru MAX? I mean, where I can type in a number for snapping and get exactly what I want instead of toggling between off and two presets?
Intel i7-5820K 3.30GHz (overclocked to 4.6 GHz), 128 GB RAM, Nvidia GTX 1080 ti 8GB, Windows 10 64-bit, dual monitor display