Thanks it seems to work, there was another article that claimed it couldn't work because dd-wrt works on a copy of the variables so the bootloader won't see the update. Appearantly that isn't true anymore.
I did install dd-wrt, and add the options to reset the partboot... after that reboots work (well i only tried 4 times... before that is would about survive one boot and reset after a 2nd boot.
Btw. you need to upgrade from cisco 1.0.14 not the later versions.
You mention that you've also set up multiple SSID's and VLANs. Can you share anything on this? In my case my device froze up on me (no more ping/anything else; required 30/30/30) whenever I changed anything particular on the LAN side of things. I would like to know if this is specific for my device or linked to a specific version of firmware.