To be honest i am a frequent player since last version and just came back after a year of break and I don't see any improvement on the site usability, few comments:

- Regardless of version 1.0 or 5.0 the same issue persist especially when you are using VPN where IP might alway be changed (regular or blockchain based one): no clear message on why the login failed the same stupid message appear "we can't find your account information" while it should say invalid username / invalid password please be specific on what error should the user need to correct it instead of being too generic and keep blocking the IP after one or two tries because of partly your fault (not providing exact error to have the user correct it), you might be saying it's a security feature/DDos protection etc... but i can say it's stupid mechanism please develop something smart (I never have any issue with other sites on the log in thing).
- This "You are authorizing with unknown device. Check your email for further instructions" never come.

- The same slow performance issue playing with web browsers you can play few rolls but can never trust it to leave it in auto roll mode (don't ask me to do the same thing regarding to cache/browser etc.../ i work in IT)

- The same behavior using API betting in which it will slow down after time to time and your team have to reboot the server to get better performance and it can last for a short time before the same thing repeat, i don't know what you have been done to make it 1.0 become 5.0 beside typing the version number.
 
- The same chest bug since last year, i think they i've changed the text from CSNO to Crystal...but the stupid code behind might intact. That's why the same behavior appear in both old and new version.