Welcome NuArcher ! You will have a blast
And I am sure you can convince your wife once she seems how much more stable it is with the two amas vs a stripped down version!
https://www.youtube.com/watch?v=p9Yk-bZLYg4 check this out for how to get the drive to lock in. Basically you need to look at that little front piece of plastic to make sure it ends up sitting on top of the mirage drive well, and keep the drive level and straight down. (note when the drive is level, the fins will not be going straight down, as you can see in the video). The older models were a lot harder to get the drives in, but you will get the hang of it. Once it is inserted, I used to (in my old 2012 model) grab both pedal sticks and try and move it back and forward together and I'd know very quickly if it was locked in place, or wobbly and not secured properly.
Unfurling the sail, if there isn't a lot of wind it can get a bit sticky. I usually just grab the sail by hand in the point where the main sheet goes through the eyelet, and pull by hand out and give it a little riggle, and it will come out good. However, first thing to check is make sure you have the yellow furling line uncleated, because if it is cleated, you won't be able to unfurl the sail out! Check out this video too
https://www.youtube.com/watch?v=ZqMQE0tbfQI (particularly look at 4min 35sec)
I find the sweet spot in my tandem island is 5-12 knots of wind, any more than that, and it is quite hard work, particularly if inexperienced. You can go out in stronger, but better to furl the sail a lot (or completely) and pedal until you get your confidence up. Keep at it! Sailing didn't come naturally for me either and the Hobie Island is a really great craft to learn the basics whilst having backup plans of pedals and paddle if you need it!