We're aware of these issues, but it will take some effort to fix! Tumblr started implementing an entirely new palette system which does not use the previous small selection of variables. We will have to get creative to programmatically map the old system to the new one.

I am hoping that I will be able to solve this by the end of the month.

In the meantime, we've manually updated the built-in palettes for the new system, so at the very least popular options such as "circa 2016" (AKA "Old Blue") should be fully working.