A possibility for the Ouvre le Chien lyric is "barking mad" or "mad dog". Then "open the dog" would mean let it all out, encouraging the insane asylum denizens to express themselves. Many therapists prescribe art to the mentally ill, as expressing themselves using art is regarded as therapeutic.
Explanation For "Zane"
Think sane, now a Z is like a lightening bolt, which ive heard Bowie uses to symbolise insanity (Alladin Sane), clever and "neat" especially as Z is like S back to front.