hey
i have just finished building this kit
the 5 springs are 4 for the corners of the bed and one for the z axis opto. if thats unclear let me know and i'll try to be a little clearer.
being honest i cant remember the flash rate mine was before i updated the software but im pretty sure the flashes at the start are just arduino booting up and starting the firmware.
my nozzle is prob about 1/2 cm from th bottom of the carrage, maybe try screwing in the oak a little less?
if it clashes with the bed you might have a problem but nothing should be above the nozzle anyways, though you might have to countersink your bed screws.
let me know if i can be of any help
thnx
brian