In the latest alpha, my dead keys (set up with Ukelele: http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=ukelele) produce a snippet completion dialogue and have therefore been rendered unusable.
This is problematic because it means not only can the dead keys not be used for their alternate purpose, but they can't even be used to insert the unaltered character.
Best, Garrett