Stop Stylevars from overwriting?
 

Is there a way to stop Stylevars in a mod from overwriting what is set when the product is updated? For instance, say I installed a product that installed a a new Stylevar, which defaulted to a grey background. To suit my site, I changed the color to blue. When the mod has an update, and I install it, the Stylevar gets rewritten to the mod's default.

Is there a way to prevent this?

When upgrading the mod you should allow the over right radio button :

Generally this will allow all your settings to remain the same, Although i have come across a couple of mods which seem to ignore this setting so the other way of doing it would be to copy the edited css into your additional.css.