Does using frozen coconut milk lead to poorer consistency than canned?
Jennifer Frazer experimented with frozen coconut milk and wrote about it on her blog.
The conclusion is that you can freeze cococnut milk. The taste is preserved, but the consistency is not.

Jennifer writes:


  The thing is, you can still use it just fine for purposes that 
  don’t depend on coconut milk’s texture or consistency;


Coconut milk is an emulsion of oils in water. To freeze and thaw the coconut milk is enough to affect the emulsion. You can compare the situation to cow's milk. Cow's milk is also an emulsion and the mouth feel will change if you freeze and thaw it.

References:


Jennifer Frazer's blog
A paper on the stability of the emulsion in coconut milk.