Is something not working like it should? Let us know.
No matter how many times I change the colour, it reverts to blue.
Hey Dan, the color of persistent alignment guides can't be changed at this time, the option in Pixelmator Pro preferences is for the smart alignment guides that appear dynamically when moving objects. Though thinking about this, it would certainly make sense to allow changing the color of the persistent guides as well. We took inspiration for the options from Keynote, which also doesn't allow this, but we'll add this in one of the next few updates.