I'm not sure if I should post in the bug forum or here, but I don't think the issue has been addressed on the forums so I want to put something here. I've heard a lot of people complaining about it, so it's not just me.
After the NWN update a few months ago, the game regularly gets extremely laggy at the same time of day. Sometimes, I desync from the server immediately after login, making it impossible to play. The lag usually happens anywhere around 5 pm to 8 pm PST, and usually clears up after half an hour to an hour.
When the issues start, sometimes I also have trouble loading the nwn server list.
I don't believe it's an ISP issue with Arelith, I've had ISP issues connecting to Arelith before and time of day did not impact it.
I don't believe it's an issue with servers being crowded either, because I experience this on the Guldorand server even when only 20 players are on.