I do have one question about the last "sketchy" part of your post Olllllo. Are you saying the laptop like brick power supply cord - which appears to come with the board doesn't connect directly to it without fiddling? That seems odd so I think I'm missing something there. It looks like it connects directly in your photos. Thanks again.
The Mirai Solutions solution implies (by way of the picture on their site)that the connector between the PS board and the PS brick (female jack) are included. It is not. THey maintain that the connector is usually included with the mini-itx case/ barebones set up.
That leaves you with 3 options: Build, Salvage or Skip.
it by buying the appropriate female connector from RS, soldering wires to it and either soldering or using connectors to affix it to the board. (Watch polarity!)
a connector set up from a lappy or a DC powered mini-itx / atx set up. (not likely)
it by feeding the Male connector from the PS Brick through the case, tying a big ass knot in it so that it cannot slip back through (strain relief), clipping off the male connecter, stripping the wires, attaching connectors (or soldering) and affixing them to the board. (Watch polarity!)
I chose Build
because it makes it easier to unplug in the event I have to pull it off the rack.