the competition rules does not restrain a size of participating teams. However, please note that one person must not belong to more than three teams.
A team leader should create an account for the team. All submissions of solutions, as well as the submission of the report for the team, should be done from this account. Please make sure that the final report contains names (and nicknames from the Knowledge Pit system) of all team members.
In future we plan to implement an internal system for defining teams from registered participants... :-)