Edit: it's late, sorry. I realise my first bug has been talked about above. No amount of enabling and disabling works. With SC off I get the weird extra dlink network too.
I needed Vlan tagging for my new ISP, so dlink support told me to go to 1.07 (WW region). So far I seem to have come across two nasty bugs.
To my dismay I have had the guest network on AND unsecured since I flashed the firmware. I have recently moved to an apartment with many dwellings in all directions, so this is a problem. We have an unlimited fibre connection, and most internet is capped in New Zealand... you get the picture. What's worse is that it's DISABLED in the router config (I never once enabled it). I know it's me because it goes down when I reboot the router. For now I have set a password, but it's been unsecured for a week. I have so many wireless networks nearby I didn't notice it at first. But there it is, a big fat dlink-guest for everyone to see. I'm using smart connect, but disabling that does nothing to the symptoms. I don't want a guest wifi network using up the router resources and wifi space (it sits right on the same channel as my main network).
Secondly I have a repeatable bug that took me a whole day of troubleshooting. After flashing the firmware and hard resetting the router, the initial setup wizard asks you to set an admin password. If you go back and try to change this from the GUI after the fact, you are permanently locked out of the router, and have to hard reset again. You get to find that out after configuring the whole thing and finally needing to reboot. Then think you're going crazy for getting it wrong. Also if you use a complex password on the initial wizard, the same thing happens. I was finally able to set it up on 1.07 with a less complex passphrase made up of simple words and no numeric or special characters.
I need the vlan so can't downgrade. Should I be trying 1.08?