How are you adjusting reinforcement to reduce maladaptive behavior? How are you using reinforcement to build a successful set of break behaviors that can be used in future environments?
Even after designing the environment and the visual supports and prompting the student to those natural cues that will stay in the setting, it is imperative that you frequently reinforce the student socially for using the cues. Are you using labeling and social praise to make the contingency between desired behavior and reinforcing consequence clear to the student? Are you making sure that the student gets what he wants as a result of using the supports? If the student wants specific time with a co-worker, is this earned for a short interval at the end of the day for following the break system? Consider whether and how to use powerful reinforcers at the end of the work day (or end of a class period) for meeting instructional expectations.