It's not against the rules, actually there is nothing about multiple accounts in the rules. Staff don't really like it when people spam a ton of accounts, because half of the time peple don't use them and it just clogs up the server. Or they use them to troll and annoy others.
I personally have two, so I can multi-task and watch over both of the roleplays I own at the same time. It comes in handy. Personally have asked a staff member this question via pm not too long ago to double check. (I can quote with screenies if you want- xD)
On another note, I still experience some lag with this new patch- I have trouble running multiple windows anymore, which makes my earlier statement about multi-tasking very hard. Such as keeping an eye on two roleplays at once- or being ingame and having map maker opened in another window. It's.. hard to do now. :c
Does your username have any odd characters like underscores, spaces, hyphens? I've noticed in game certain symbols in usernames and maps have turned into gibberish pixels. The ones I've noticed the most is - and ~
Maybe that has something to do with it?