Bitkonan is not closed at all, but their services rend to fail frequently. This is a major reason why many users frequently think it doesn't work. The fact is that it do really work, and it's active but we must be lucky of finding access at the appropriate time.
In general terms, this is a basic platform. It works providing trading activities among a considerable number of tokens. However, it is the root of discard among exchange because of tracking a unstable value in the orders of sales. It means that it does not fail in volatility, but it neither works for liquidity.
On the other side, users have also reviewed it as a difficult platform to trade in, it a project without solid features. While other users think it is a great page. In conclusion, there exist different opinions about it. I just suggest to give a try but by investing little amounts of tokens. If you find it does work, then you can use the page.
NOTE: Consider the negative aspects before investing on it.