The cranks are going to require a French puller to get them off to service the bottom bracket. I don't think anyone sells the tool any more, so you will need to check older bike shops to find one.

Tire pressure is a function of tire and rim size, so narrower tires require more pressure. And unlike a single bike, the tandem typically has more weight on the front end due to the weight of the captain and the length of the frame.

Take it out for a few solo rides to get used to shifting and braking and the long wheelbase before taking your stoker.