RW7 Minify CSS ignoring global code

I’ve just upgraded a site to RW7, and whilst everything appears to have gone smoothly, and works fine, the global css (Settings/Code/) isn’t being applied to my pages: I have to uncheck minify in the Advanced settings to get the global CSS to be applied. Is this how the minify works? Should I only use the page-field for custom CSS, or is this a bug or potential issue with my site / setup.

Great job with 7, btw: like the streamlining and interface tweaks.