thanks for playing :D, yes the invisible walls is making people behind it looks like possessable (since there is no sign) and that is a problem that I did not figure it out when developing. xD FIB agent is priority. Yes about the driving car, since the car speed is vary, only way I think to prevent crash is to make the car behind it use the same movement speed of the car in front of it.
If you interested in this game and don't want to miss information about the game, you can also follow Good Spuun on twitter :D (Good Spuun (@GSpuun92889) / Twitter)