Perhaps I should have introduced myself first but I wanted to make sure and share this solution while I was still thinking about it.
I have the WRT54GL with 16MBs of memory. I installed the latest tomato (1.28) then installed the Neorouter firmware and everything appeared fine. I could login and create a local network for machines. Since that kind of defeats the whole purpose of a VPN I decided to try connecting from outside my LAN. That's when I kept getting the hr=0x80072749 error over and over and over again.
I should probably mention I inadvertently installed 1.3 even though there's 1.4 right there on the download. I guess I wasn't paying attention.
Anyway I was turning off all kinds services on the router changing all kinds of things for hours and hours. I kept noticing the reported free memory always seemed really low (down to 5%).
So finely, not expecting it to work, I disabled the routers wifi/wap ability all together and tried again and it worked (available memory was upwards of 1MB).
I had already disabled as many services as possible on the router (the bandwidth monitor, auto-refresh on the system/overview screen, ssh and telnet of course and a few others).
So if anybody still using this old 16Meg model WRT54G is having this issue try freeing up as much memory as possible and trying it again.
By the way, and sorry for the off-topic, the WiKi for installing "neo-router-in-a-box" needs updating or more specifically the OpenWRT portion refers to this:
Quote:
http://www.neorouter.com/Downloads/.../
But the URL doesn't actually have a URL. It's just the "/.../" literally...