We are aware that Visual Style Builder does not work really good in Chrome and Internet Explorer. I have tested your scenario with Chrome and could confirm this is a bug. It is a high priority to make the tool works fine in all browsers, so in the next few months we will do our best to fix most of the known issues.
For now I will recommend to use FireFox when using Visual Style Builder tool, I have tested the same scenario and it works as expected. Color is changed, saved, go to another Control, do the same, go back to the first control and the change is saved.
Visual Style Builder test with Firefox
shows is s short video file, showing my test with Firefox and Metro skin color changes.
the Telerik team
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