To get to HS from POP:
Leave POP via Century Drive
Turn left onto Victory Way (Turn left at the traffic light)
Take the next right, this ramp leads directly into Hollywood Studios.
Signage is not updated within POP Century Resort.
As far as making it difficult to get back from HS. Disney actually tries to discourage any type of personal driving while staying on property. This is why there is the busses, boats (for other resorts), and monorails (for other resorts). Yes, Disney Skyliner will have direct access from POP/DAAR to HS. Without including any wait times, the trip via Skyliner should be less than 15 minutes.
If for whatever reason you wish to drive, please use the navigation app Waze. It is updated by Disney to keep the roads updated and road closures accurate.