ref "bump, help": 1st of may, noone is here (except me now that I'm taking a break from my adventures in ZFS and the weather sucks so I don't want to go motorcycling and can't fly my RC helicopter... *sigh*)

It cannot load the netfilter modules and thus cannot do NAT and thus returns error (which leads the frontend to tell "failed to start").

Which kernel are you running ? Note that I'm not sure lehtos kernel actually has netfilter compiled in (it might be just overclocked), and it might be that lehtos kernel uses the same version string as stock one (IMO *very* bad form). Anyways the kernel you are running is reporting same version string as stock one so if it's not the stock one the kernel packager is committing a sin by using same version string.

Try installing titans kernel-power, it also can be overclocked and is known to have the required modules (remember to reboot).