Rob Youngblood ( Keeper James) also played the sheriff in episode 3.15, Paradise Lost.
The hall of the monastory was previously used as the Visitors' ambassy in "V:the final battle"
The unit Diana was modifying with a laser to store the data is an RCA CED disc player, a failed consumer video format. There were many laser disc players (and laser discs) in the lab, but they probably did not want to dismantle one of the far more expensive laser disc players to use as the prop.
Austin Nichols (Seth) also played the leader's son in The Walking Dead's Alexandria.