I'm going to leave these all locked once they are resolved, and edit them into this topic, as a help library (I won't delete them because I don't think people wanna lose post count). Please try to read this before posting a new topic. Feel free to post any improvements too.
Please also read Vivi<3's Guide, answers far more questions.
For any questions regarding the game hanging/freezing: Linky
1) Guide to the "Already logged in" glitch:
What you need to do is go to RoadsideMS's web site, http://22.214.171.124/main.php, and log into the site.
Then Go to UserCp>BugFixes>Unstuck Character.
Then you will enter your Login information and that usually solves your problem. If not that, possibly check the chatbox on the website and see if I or someone else can help you.
2) Error 38
Clean your v62 folder. This error happens when a bugged character appears on your screen, your folder is not able to "handle" this bugged character's appearance. Therefore, D/C's you.
3) "Can't Login to Main Site"
Just wait a while, not really sure why this happens.