Try clicking on View/Display Settings/System Colors, then the System Colors menu will pop up. In the Graphics tab, near the bottom, click on the color icon next to Background and change the color.
That is pretty high vibration level (maybe this is relative). Anyhow, I am using a 3" plate of Al directly mounted to the vibration table with hardware. It is only protruding out about 3", but I already found a natural frequency at around 1000 Hz. Stiff in static mode might still be too soft...
I have used TC100U-15 thermal conductive (electrical nonconductive) gap filler adhesive from Saint-Gobain to bond down a board (along with hardware at the corners). The board passed a 90g for 5 minutes vibration test. The thickness of the gap filler is .015". The board has all mil-spec parts...
