@Khaleesiscript is working really well, however I am ending up with lots of very botlike usernames. It seems to enter 4 digits only and then select one of the autosuggested names.
Would you be able to improve this please? For example, allow us to define a list of usernames which we have generated and pick at random; if it's in use it could then choose another from the list. Alternatively you could come up with a generator based on real data from the highscores or a username dump etc. Would probably be better and less likely to attract attention if the user could control though.
Thanks!