Hi
I have only just got my DHP-307AV, so I am by no means an expert, but here are a couple of tips.
Powerline adaptors are only compatible when they are the same speed, so the 500AV is not compatible with the others. Get a refund or sell it on eBay.
To communicate all the adaptors have to have the same encryption key. Try putting all of them on the same mains extension lead so they are right next to each other. Set all the adaptors to the default encryption key using the D-Link Powerline software. Do this by plugging them one at a time into your router using an ethernet cable, start the software, wait until it sees all the adaptors, then set the encryption key of the local device to the default by ticking its selection box and then clicking the Use Default (public network) button on the security tab. Close the application, move the cable to the next adaptor....
Once they are all communicating - press the simple connect button on one adapter. Wait a few seconds then press the simple connect button on each of the others.
Good luck.
Steve