The upgrade to 4.0.2 seems to have broken my custom color scheme created with 4.0. I can still see my custom scheme files located at ~/Library/XamarinStudio-4.0/HighlightingSchemes. However, it now doesn't show up in the color scheme list under Preferences within Xamarin Studio. If I try to re-add the scheme using the "Add" button, nothing happens... no error, nothing new shows up in the list, etc.
I noticed that if I export one of the existing schemes (e.g. Monokai), the format seems to be in JSON now as opposed to the XML format before? However, I also found that if I set a new name and tweaked some of the values in the scheme I exported with 4.0.2 and then re-added, nothing happens, same as before.
Seems like the importing color scheme's are broken?