How to pxe-boot on PC Engines Alix2d3

Dear all,

I have a question that concerns the pre-configuration required for PXE booting on Alix 2d3.
Basically, what I have tried so far, after installing dnsmasq, is adjusting the configuration file /etc/dnsmasq.conf, where I simply uncommented the following commands:
dhcp-range=,,12h (I adjusted the addresses accordingly)

Following that, I put the ramfs image file (OpenWRT image that I built previously) in /tftpboot.
However, when I try to boot, I get no options to boot with PXE (I did press N after connecting Alix as I found it should be done), the board simply loads what's on the CF card. When the card is removed or if there is nothing on it, then nothing happens.
Is there some part of configuration that I am missing here?

This is the tutorial that I was referring to for the most part:
Thank you for your input.