This mod does not appear to be available on CKAN for download, despite it's presence on SpaceDock/Curse.

I'm wairting for Bizzy to update toolbar to 1.1.3

Hopefully this will fix it

I should say, that it's not being marked as incompatible - The mod isn't even showing up when I set the CKAN filter to All. (Mod name search: Interstellar or Mod author search: FreeThinker)

That's due to KSP-CKAN/CKAN#1695

EDIT: Sorry, getting my bug reports mixed up. I don't believe the cause of this bug has been tracked down.