The bolt and carrier will likely be configured similarly to the AK bolt and carrier, which a short carrier and a long stroke piston coming out the front. Now as far as the bolt goes, look at the front of an AR bolt and re-position the ejector to the 12 o'clock position and the extractor to the 6 o'clock position. This will eject the case downwards. Now obviously the bolt carrier has a very long (relative to cartridge length) travel of about 2-1/2 magazine lengths, meaning that when fired, the the bolt travels backwards and clears the back of the magazine by at least 1 whole magazine length, allowing the spent and live rounds to be extracted and ejected downwards at the rear of the rifle. I do not know how the firing sequence is initiated, if it is by hammer or striker, but that it not that important at the moment.
AK carrier:
versus an AR carrier:
And an AR bolt face. Rotate it 120 degrees counter clockwise and that what is would likely look like.