maybe wax is part of the castor and gets solid at a certain temp causing the cloud
The wax (or known as gum in the castor industry) is one of the parts of the castor that provides it's unique high temperature lubrication property. Typically, the castor oil that undergo more de-gumming burns cleaner but does not have as much lubrication protection at high temperatures.
I have seen some synthetics cloud with some race fuel that have a low specific gravity or a very low aromatic content.
Try mixing petroleum based two-stroke oil with methanol or ethanol. It will also cloud up or fall to the bottom of the container like a rock because petroleum will not dissolve in alcohol without another chemical that will help the oil dissolve.