Ways to Avoid Bugs:
Stay out of rooms with ghost items! Ghost items are items that are dropped by a player (or enemy) and are picked up by someone else and is still seen on the ground by other player. This bug itself can cause the room to become bugged and can lead to bank issues, vanishing items, and ???? bug. When you notice this bug, leave the room and start a new one as soon as possible.
I don't know if this actually helps but....I normally transfer items with a second account over common bank. I know people who use common bank and have no issues and then people who use it and do have issues. But it is a preference not to and I have almost never had a bug here. (I have been here almost 3 years too)
Take screen shots of EVERYTHING!! Why do this you ask? If something does go wrong it can be fixed!
Avoid rooms where you DC a lot in (once meh happens but if more then say 2-3 times in a short time span then probably not a good sign). If you are in one of these rooms you should probably not go in there because it will cause issues such as: Items vanishing, Bank issues (such as bank ???? items and vanishing items), and the infamous ???? bug. If playing with friends it is recommended to remake room or sometimes having a new host for the room can help.
I personally do all of these and I have only had the ???? bug once the entire 3 years here =P