your settings seem to be correct, how much time has passed since you added the records?
Depending on your domain provider, the changes can take up to 24-48h before showing effect.
Most providers are quicker than that, but they all need some time to update the records.
Well, I have set TTL to 600 (seconds), so it should be. Also, before there was another temporary page there showing. This one is not showing anymore, which means the DNS changes have been applied.
No, you can have other A records as long as they have no “@” as their name.
But seeing your screenshot, I recommend connecting your domain with a “www.” preceding it and seeing if this resolves everything. Note how Option 1 says “if you want this domain to redirect to www. …”.
Adding the domain with a www before, then hitting “Check Status” might help.