Not sure how to do that by reading values from the Options Page as you describe, but here’s an alternative:
- Create a custom post type called ‘Colors’
- Create one post per color with a single Color Picker field
- Use a Relationship field to display all of the ‘Colors’ posts to choose from
Just wanted to confirm this exact issue with ACF Pro and provide a temporary workaround. You can deactivate (but do not delete!) the Post Types Order plugin temporarily if you need to edit any of your ACF Page Links fields. When you go back to reactivate the plugin, your post orders should be restored.