Check your battery terminals!
All the warning lights including RSC are simple symptoms of the van losing power. Since the vans use engine driven vacuum and power steering boost, that's why those go out too.
It would be VERY unlikely for random stalling to be caused by anything other than loss of electrical power. If you still had battery power, and switched off your ignition, you would still have brakes and power steering because the transmission would stay in gear and spin the motor.
The alternator actually doesn't run 100% of the time (heat / duty cycle) so that's why a bad battery connection can cause it to stall. That said.... running too long with an intermittent open circuit at the battery can damage the alternator.
It only takes a momentary break in power to shut off the PCM. If you were watching the dash, you'd probably see it flicker.
2000 E450 dually V10 wagon