calculating waiting time for a person in a box variable

[japrap]

hi everybody

i want to know how much time a person wait in a box variable ?
for example in the attached model i want to know how much time a person wait in box2 before enter to box3 ( i want that if a person waits more than 4 hours he doesn't enter to box3)

1.mdl link :
http://s000.tinyupload.com/index.php?fi ... 6170771439

[Administrator]

Can you use a queue instead of a level? It's tricky to identify individuals when they are in a level.