For sure or basing up with my observation is that this is a fiat based casino and now they had accepted crypto(correct me if im wrong) if you can see those fiats integrated on the site
Correct, they added the crypto support after fiat, so the experience will differ from casinos that tailored mainly for crypto.
According to the rumor, they are already working to improve the site. However, it's been a few months and still "coming soon (tm)."
They actually have a different domain for a different country, I don't even know their other domain. For example, in twitter their site is for the UK. Until now, still don't know a full detail for the list from BK8.
I don't know why they not using one email for all.
I believe the only different site is the UK one because of the license. So it's basically (1) UK site and (2) The rest of the world except blacklisted countries.
For the (2) rest of the world, you can use the same login info on any of the mirror sites, for example: bk8btc.com and bk8play.asia
It's recommended to use these two domains, and if you aren't sure about the legitimacy of a mirror site, you can always ask here.
Tips sir