If you live in the UK and If you're not having any luck with support and your queries are going unanswered, I suggest contacting trading standards. There are new laws in place to prevent being passed from pillar to post when buying digital content. I contacted ZoS around 48 hours ago and heard nothing. Looking on their forums there seems to be an issue between buying on LIVE and getting your crowns. It's a lottery whether you'll get them or not.

Shoddy customer service isn't acceptable. Some other people have been told to provide proof of purchase. WTF? That's up to ZoS to have something in place between themselves and MS. If the game recognises you have ESO+, then it should recognise you receive or should have received crowns. Thus both systems can communicate with the other. Paying for eso+ isn't a charitable act. If I pay for something, I expect to receive everything that's been advertised within the membership.

The support page seems to be down now, so you can't even contact them via their own support page. Would some from ZoS care to comment where we stand with regards to getting the crowns we paid for in good faith?

Someone should really take this up with the BBC (watchdog) as there is obviously a long standing issue between ZoS and LIVE and the feedback from ZoS is non existent. Just google the issue. There's pages of people having had the same issue - all on LIVE.