The swf_onCondition() function describes a transition that will trigger an action list. There are several types of possible transitions, the following are for buttons defined as TYPE_MENUBUTTON:
IdletoOverUp
OverUptoIdle
OverUptoOverDown
OverDowntoOverUp
IdletoOverDown
OutDowntoIdle
MenuEnter (IdletoOverUp|IdletoOverDown)
MenuExit (OverUptoIdle|OverDowntoIdle)
IdletoOverUp
OverUptoIdle
OverUptoOverDown
OverDowntoOverUp
OverDowntoOutDown
OutDowntoOverDown
OutDowntoIdle
ButtonEnter (IdletoOverUp|OutDowntoOverDown)
ButtonExit (OverUptoIdle|OverDowntoOutDown)