When McKay had his personal shield in an earlier episode, it prevented him from eating and drinking as long as it was activated. Not a problem for Lucius in this episode.
John Sheppard is able to use the personal shield that Lucius has already activated and used. However, we learned in Hide and Seek (2004) that once someone has activated a personal shield, it can only be worn by that person.
Colonel Sheppard, when attempting to save Lucius Lavin, has a P90 equipped with a suppressor. Later on, he is shown with the regular SBR version of the P90. Although suppressors are removable, it is unlikely that he'd remove it while trying to stay hidden.
Many times, the shield device worn by Lucius goes from being lit to unlit.
Around 31 minutes, one of the villagers comes to Carson, Rodney, Teyla and Ronon with four bowls of stew and gives one to each one of them, except for Ronon. The scene changes from them to the villager and then when it changes back the villager is holding the tray in one hand with no fourth bowl but Ronon clearly didn't get his bowl.
Ronon does have a bowl in his hands at the end of the scene, but how he got it, is a mystery.
Ronon does have a bowl in his hands at the end of the scene, but how he got it, is a mystery.
The bars of the cell holding the team in are welded, yet there are no indications of electricity in the village, which seems to rely on candles for light, but people used welding torches long before MIG and TIG welding. It's also possible the aliens on this planet might have other technology, or perhaps they traded for the cell-door or welding equipment with people from another planet.
The pallet dropped on Lucius' head appears to be from Earth, complete with knockouts in the rails for the forks of a forklift. However, there can only be so many ways to design a pallet from flat wood, so the 'knockouts' are not surprising. They could have been (and probably were) designed to allow the pallets to accommodate spars or poles for carrying them.
After Lucius Lavin comes up from being held underwater by the Genii, soldier his hair is dry. This would make sense if the personal shield would be "air" tight. The shield would be a barrier between the water and his hair and skin. However, someone inside the shield has to breath so it is presumably designed to be permeable to gases, but not solids or liquids.
When the ruffians come into town, as Sheppard and his team are leaving, and take everyone hostage. Just before Sheppard's team lowers their weapons, there is a close-up of the revolver pointed at him. It is very obvious that there are no bullets in the gun, you can even see light entering the chamber from the back.
If the 'ruffians' are members of Cowen's personal guard unit, they should have been with him that day when he was vaporized in Landon's nuclear coup.