Hiring: Signed a Contract to Start Work, then Was Told That I They Will Be Review It

My question involves labor and employment law for the country of New Zealand; regarding my employment contract that was signed by the company and myself then revoked based on an error that i had made on their online application website. I had thought that by being entitled to a clean slate policy agreement, i wouldn't have to disclosed any of my criminal convictions that had happen over 25 years ago and that last conviction was over seven years ago...
When i filled out the contract that they gave me, i said that i did have a criminal conviction and they decided to cancel the contract...
They told me not to come into work until they reassess their decision two weeks later, they said based on me not disclosing my criminal convictions they where not going to be employing me.

Am i entitled to any compensation?

Why are they paying me when i haven't been working for them?

Why has the employment union ringing me to let me know if i had signed up with them?

Why is their insurance company saying that i need to give them my insurance option?

They are paying me after they have said to me that i haven't got the job are they giving me a 30 day entitlement payout due to me having to find another job?

Hiring: Signed a Contract to Start Work, then Was Told That I They Will Be Review It