Hey @bitlogik ,
Apologize for the late response. Have you tried plugging the fuse-support interface? If not, you can take a look at the interface documentation as well as this discussion about the use of the interface. You can use snappy-debug to get suggestions/understand denials. If you run into problems, feel free to post the snappy-debug output here along with your questions and we are happy to help.
If you can make your snap work with this interface, it could be made strict (and therefore enjoy all the benefits of a stable runtime environment). Please remember classic snaps are not installable on Ubuntu Core devices and also run in the global mount namespace, which means great care must be taken for the snap to work reliably across distributions.