Does this firmware increase the DHCP reservations? The one thing I hated when I went from a DGL4300 to the DGL4500 was the small reservation limit. I have around 50 devices on my network and with the DGL4300 I didn't have a problem with the number of reservations. But the DGL4500 for some reason has a paltry limit of only 24.
That's a lot of devices to connect to a single router. If you are connecting that many, maybe you need to find a new business class device or something to handle that load. These are home routers, not meant to connect more than 20 or 25 devices max. What some of you people do, is going above and beyond. If it fails, well...then that's on you. That's more user error than anything. Again, it's a home class device, not meant for THAT many devices. With that many devices even, you could still cause the router to malfunction, from so many connections. On average, each device MAY have at least 50 or more concurrent connections.
I will definitely say that there are MANY problems with this firmware. Hence why a lot of people are having issues. A lot of which you people thought I was crazy, when I experienced them and reported back. Go figure right?
And as stated earlier, you cannot downgrade firmware.
Now, I will say that a lot of you have provided a LOT of good feedback. One of the biggest problems I believe is to be the UPnP not forwarding correctly, regardless of the NAT filtering settings. This is a problem. One being, because it can flood the table, and cause your router to lock up as you have said. And two, it can cause connectivity issues as you have seen (such as locking you out of the GUI/requiring a hard reset) via WAN and LAN and even over the WLAN.
Cooling these routers is another big thing too. If you can, bust out the stand that you have, and set the router upright. The antennas should be like a T shape, while it's standing upright.
My suggestion is to just be patient while waiting for a fix.