I can report that tomato-K26USB-1.28.0489MIPSR2-Toastman-RT-N-Std.trx seems to work very fine indeed on the F7D4301 (v1). No problems at all to flash the .trx-file from the web interface. I forgot some of the basics though, like powercycling, clearing the nvram, disconnecting everything but power & pc and whatnot. Thus I had some problems until I realized the router still used the same old ip, username/password, ssid and other settings and not the standard tomato/toastman ones (no dhcp etc). I cleared the nvram from the tomato gui and now everything is super.