I’m glad you and your wife enjoyed the game!
To answer your questions:
- Yep, when you reach the end of the adventure, it ends and you get all of the benefits. One thing I’m not sure is sufficiently explained in the rules is that calling the adventure home is intended to be taken as part of the Hire adventurers action, so it’s something you choose to do after adding a number/X to the track.
- And yes, you can benefit from the the technology if you buy it on the first action. Obviously the two when doubles are rolled tech don’t have any effect on your current turn because they only work when the dice are rolled, but you can take advantage of the other ones on the same turn they are bought.