I agree with you about finding objects that aren't solar system objects or Messier objects. This, in my opinion, is a weak area of the app. What if someone doesn't know the names of things to view? Wouldn't it be better if we could at least scroll through a list of viewable objects in the sky at the moment? Obviously, a more graphical interface like we have for the Messier objects and the Solar System objects would be even better but just a list would be okay. Maybe add-on packs for the app?
I also use a Surface tablet with ExploreStars and I have no problems so there must be something wrong with your particular tablet/OS or you are doing something wrong (which is easy to do and expected for someone new to the system).
As far as your other problem, it sounds like you might be losing connection with the mount. The obvious reason is because you have your tablet set to "Always Connect to this Device" for your home's Wifi. You must uncheck that option. Even better, set your mount's Wifi to "Always Connect..."
My guess is that will resolve the connection issue.
Explore Scientific iEXOS-100 and EXOS-2GT (non-PMC)
Explore Scientific ED 102mm Refractor