Edit: Fixed by shift clicking carbonite minimap icon
I've decided to embedded the minimap into carbonites minimap (I've had it working in the past but couldnt get used to it - still I'd like to try again).
I've allowed Carbonite to move the minimap buttons into its own frame. The problem I have is that the buttons are tiny (as in 4 or 5 pixels wide) and placed one above another, with a correctly scaled carbonite "C" icon obscuring them entirely.
I've disabled other mods and still have the same problem. I don't know if the problem is with carbonite, carbonite settings or some hangover from another mods mucking around with layout-local.txt settings.
I've tried adjusting the minimap button frames scale, but that's just made the jumble of pixel sized icons use slightly more pixels. I've also played with various minimap scaling values in the Map Minimap options panel, to no avail.
If I leave the icons around the the minimap they appear to be correctly scaled.
Edit: Fixed by shift clicking carbonite minimap icon