I got to do some testing and have fed this back to Adobe.
If others are finding the same....
When I tried to use a 32bit ANE in my project I received this error when running the release build.
"The required native extension is missing for this application. Try re-installing or contacting the publisher for assistance".
This makes sense.
I attempted to therefore build a 64bit version of the ANE.
However, FlashRuntimeExtensions.lib in the SDK appears to be x86 only.
I confirmed this by using dumpbin FlashRuntimeExtensions.lib /headers
I am assuming that ANEs are not yet catered for yet