I'll offer a first session start hopefully without providing spoilers: the important thing is to obtain a working Moon Lantern. Moving in both levels of the curse becomes possible (potentially trivial).
Entering from Grymforge, engage the Harpers, travel to their safe haven. Explore the Inn: This varies pending on actions in Act1. Upon leaving accept offer (this requires a trigger inside the inn, may not be available under certain outcomes in the Inn). End result can vary depending on choice (obtain a Moon Lantern, or safe travel to Moonrise to obtain one).
Entering from Risen Road. Join Caravan to Moonrise (Requires Spider's Lyre). Discover how to obtain a Moon Lantern.
Not engaging either of the above the Caravan can be encountered in the lesser curse area.
If all goes poorly - force your way through. Suggest the proper resist, a fast toon (use only one), and a collection of health potion. Basically, make a dash for Moonrise.
No matter how you proceed, you should never leave the Act 2 area until you are sure you are done there. Several quest lines end and cannot be returned too if you do.
Act 2 is a bit clearer about this than Act 1. Given the nature of the game doing everything is impossible, because for numerous reasons. You can meta outcomes to your liking by saving often.
*Updated to the actual name of the Lyre required rather than associate it to just one NPC.
Last edited by Spiral_Architect; 13/10/23 01:46 AM.