I've been preparing this and just noticed that Taffy has beaten me to it. Never mind, I'll post it anyway even if it duplicates some of what he's already said.
Hi Bstar
Welcome to MoveToNZ.
Sorry to hear you're so stressed out. I think a lot of people can identify with this feeling. Timing is often critical because there's so many balls to keep up in the air at the same time and you need them all to fall neatly in order just when you're ready.
You're quite right when you say 'how long is a piece of string' with regard to applying for a WP. I've known people stand in line and get the permit the same day, whereas others have waited several months, but I think the latter was due to hold ups with medical certficates etc. Generally though, WPs are issued fairly quickly and we're taking maybe a couple of weeks at the most. If you have everything ready that's necessary for your application and especially if you have a job offer, you shouldn't have a problem. If you're only applying for a short term WP to fill in while you're waiting for your PR process to go through, you shouldn't need to wait for medicals and police certificates as they are only needed if your WP is for 12 months or more. However, if you want a WP for 6 months or more you still need to send in an X-ray report.
I hope things settle down and fall into place for you soon. You're dealing with 2 processes at the moment which would be confusing for most people.