I doubt a lot has changed since this article was posted on 20 August 2014 :
http://www.coindesk.com/bitcoin-ban-fear-fades-thailand-exchange-launch/
The last I heard of any bans on Bitcoin in Thailand was back in 2013. The last news update on one of their exchanges was in March of this year, so I guess they still active.
https://bitcoin.co.th/news/