It can't be added to our VM Templates by default. Because not everybody has this CSS file;
<link rel="stylesheet" href="/templates/@@@@@/themes/####/css/vmsite.css" type="text/css">
There are millions of different joomla templates around, and all of them are different, but FlexibleVM2Global.css is loaded in the quicklook page, so you can submit all your CSS rules into this CSS file for quicklook page.
Cheers.
Case solved, topic is closed.