Yep, this is a bug introduced in v1.7. It worked fine in v1.6. The Patio Pam event sends you to the wrong map.
You can fix this by
You must be registered to see the links
and updating the same variables that would've been updated when you visit her in the washroom. Save just after Pam tells you to meet her in the washroom and you are sent to finish the afternoon class and appear outside of the school.
- Set switch 450 "Pruebas completado" to false.
- Set switch 451 "Caza acosador" to true.
- Set variable 165 "PAM Quest" to 10.
The next school morning, you will be able to enter the air vents (like you did before) while Pam is taking a nice long shower to hunt for the peeper.