I've given up on maps.me. It was my go-to maps app for a long time.
I love the fact you can use a phone or tablet off-line and move using the gps chip to update your location.
Unfortunately, you need to re-download the whole map thing regularly and download is slow.
The maps expire regularly and you have to redo the whole thing. You can't use what you have.
Also selecting the specific areas you want is clunky. You need to use pre-defined areas, sometimes large, sometimes multiples sub-maps.
Map definition is poor at best unless you scroll down to a very small area.
I had the whole Alpine region of northern Italy, Switzerland, Austria and Germany loaded to my Android tablet just before my trip last year to the area.
When I got to Italy, a few days later, the maps had expired and I had to re-download again.

This isn't the first time this happened and I just gave up. I use google maps off-line.
With Off-line maps in google maps, they work just as well and they're good for a whole year. Just select the area you want, and go.
The only issue with google maps off-line is you're limited to the size of the area you want. If you want a region, you need to download multiple maps.
Or work online. I now have some data while in the EU.
I now only use that while visiting a city or something.
At least with a real GPS you can still use it even if the maps aren't up to date.