Other mistake: When Thor reveals to SG-1 that the Replicators have reversed the time dilation device, he says time is moving at a factor of "10 squared" (100 times faster than real time). Carter says that in the hour that passed, 4 days have passed for the Replicators (which is correct), but then says depending on when they did it, hundreds of years could have passed. But that's not possible since that means years in real time would have passed. But the Asgard didn't set this trap years ago, just recently.
Other mistake: Carter says that the chance of depositing the heavy element inside the Katow sun while the element is en route is about 1%. However, hypothetically speaking, the actual chances would be infinitely smaller, in fact it would be near impossible. Simply consider the distance from earth stargate to the Katow stargate, the diameter of an average sun, and the time it takes for an object to travel through the gate (about 12 seconds). Taking the closest star to us (Alpha Centruri), at a distance of 4 light years, this means that the wormhole takes ~443ns (0.000000443s) to pass through the sun (using our sun diameter). Similarly, taking the diameter of the Milky Way as the distance to the furthest star in our galaxy, ~100000 light years, meaning the wormhole takes ~17ps (0.000000000017s) to pass through the sun. This means that the SGC would have to shut down the gate within a a maxmium of 443ns or a minimum of 17ps time gap. As we have previously seen, the stargate takes far longer to shutdown than these miniscule time lengths.
Other mistake: In several episodes throughout the series, SG-1 is coming through a planet's Stargate but there's no sign of a MALP, even when it should be in the shot. SGC wouldn't send a team through without sending a MALP first (not only to check for a DHD, but survey the land, check for habitability, etc). And if the idea is "well, maybe they have a recovery unit go fetch it before SG-1 goes through", then why would the MALP be present in all the other episodes?
Other mistake: At the end, Anubis/Vaselov is sent to KS7-535 and we see a shot of the gate being partially buried in snow and Anubis frozen. However, the wormhole should have cleared all the snow in its path when it established, meaning it wouldn't be buried in the snow as seen.
Other mistake: In the last few minutes of this episode, Carter uses the DHD to dial home. She enters the first chevron, then the "Cannon" dies. And when she proceeds with the dialing,the first chevron is still encoded, and you can hear that she enters seven additional chevrons, which gives an equal of eight chevrons, and then engages the stargate. That would mean they are in another galaxy, referring to S02E15. In that episode they tried to dial the eight-chevron address from SGC but the computer wouldn't accept it. So, it is impossible that they would be in another galaxy.
Other mistake: When Jonas says he has flashes of what's going to happen (and no-one believes him), Teal'c says they have encountered many strange phenomena but no-one who could see the future. Except Jack and Teal'c had a whole "Groundhog Day" episode where, because they were stuck in a loop, they could see the future. Carter then says it goes against all the laws of physics as we know them, despite knowing time travel and other things that break the laws of known physics exists.
Other mistake: When they are securing the base into three zones after already going into lockdown they secure zone one. Then zone three. Then zone two is secured. But because zone two is in between zones one and three it would already be secure. They are securing the zones from each other. Clearly showing O'Neill secure zone two with a closing bulkhead door displays the incompetence of one of the other two characters. (00:29:40 - 00:32:00)