Hello. I just finished soldering all the components on the motherboard. I highly suggest soldering the components the conventional way- with a high quality soldering iron. Start with the small ATMEGA644P chip first. Then, do the resisters, capacitors, etc. Do the largest components last, for example, the ATX power connector. I found that it was best to position the surface mount resisters with a tweezers, anchor one side of the component down with masking tape, solder one side of the component, & then remove the tape and solder the other side. Work slow! Follow the pictures in the documentation carefully, as it was sometimes hard to determine if components were to be vertical or horizontal on the soldering pads.
I did not have a chance to program / test the motherboard yet. I have to assemble the USBtinyISP AVR Programmer Kit. This should be very easy assembly compared to the motherboard!