To get back to the same spot as the night before, you’ll need to plate solve and yes you’ll need to download some plate solving software - elbrus is free and many folk use it but it (can) be fiddly to get working . Others (including myself) use pinpoint which is fast and reliable and a little easier to set up. But there’s no reason why you can’t get things working smoothly with Elbrus.
You don’t need any extra downloads to focus. If you’re planning on running auto focus then you’d need a stepper focuser which can return to its absolute position. But otherwise you can just loop exposures (without needing to save the images) until you’re happy with your focus.
If you’ve got plate solving working, you can always slew off to whatever star you want to focus then slew back to your target at the click of a button.
With auto focus SGP uses the whole star field to work out focus and this is a great to achieve very good focus.
It really is excellent software and makes imaging so much easier. It’s very intuitive and easy to learn. Plus the support from the writers is quick and helpful. Personally I can’t recommend it enough!
Just to clarify as well I’m not receiving any money for these glowing endorsements of SGP I’m just a happy user (but Ken/Jared I’ll happily pm you my bank details if you like!!!)
Have a read of this as well it’s really useful: