Don't worry overly much if Maggie doesn't use something right away - I cannot tell you how many times I've bought a toy or something for my two, no one seemed to like it, and just as I was ready to take it back to the store - like a month later - suddenly it became a hit. (BTW, Petsmart is great on returns - just hang on to the receipt). And they go through phases - right now Dharma enjoys sleeping on one of the dining room chairs - last month, it was on top of the small cat tree.
And, yes, they love windows. I've got both my trees near patio doors so they can look out (why, yes, my dining room and living room are decorated in the 'feline motif').
Sometimes they just like to curl up somewhere out of the way and secluded - and she really is just getting used to her new territory. But if you can provide her a few different places to go to, at different levels, it expands her whole world.
Oh, and I bet you know this because of the dogs - please please be careful to never leave anything out that she can swallow - like ribbons, dental floss, or yarn, or rubberbands, or anything like that...sometimes cats will start to swallow them, and because of the way their tongues are made, it can only go one way (down) and sometimes it gets stuck - which can result in surgery or, even worse, death. I bet you will find yourself becoming even tidier in your living habits, thanks to Maggie. Also, always check the washer and dryer before you start a load - sometimes they get curious and crawl inside - very scary!
you are such a good daddy - btw, if you have time, read up on LawGuy's posts - he adopted a feral kitten and has gone through a lot of the same things you are - and is a wonderful papa to his kitties.