Normally I wouldn't comment on this, but there is already so much anxiousness flying around during this whole process for everyone.I also think there's lots of ambiguity when it comes to this subject also. If you leave Canada without your Canadian passport in-hand and use your previous passport, there is no reason why you cannot enter when you return. Granted you may have some complications, but you won't simply be turned away.
I say this because I lost my PR card in transit, when returning. Essentially, all I had was my non-canadian passport to say who I was. Instead of going straight home like I normally would, I had to see an immigration officer, who stamped my passport and let me through. She typed some things on her computer... I'm assuming she could see all of my information.
Ideally you should just wait for the Canadian passport, but sometimes that can't be a reality for some. Seek further advice, but don't rule out being able to travel altogether.