dghent

If you're running NINA and Stellarium on the same computer, the default settings in NINA are all you will need - 127.0.0.1 (localhost) for IP address. You *do not* need to hunt down your internet-facing IP and put that into your apps unless you're running NINA and Stellarium on different computers. If you're having issues fetching object info from Stellarium on the same host, either the API is not enabled in Stellarium or you have a firewall installed that is preventing that communication.

Computers don't "like" anything in particular. It won't know a radian from the going price of fish at the market. It's a real number, either way. The problem you speak of is a mechanical issue involving the precision that the hardware is capable of. Other mounts and, indeed, other drivers, have no problems dealing with this.

Refusal for EQMOD to sync near the meridian is a something that's peculiar to EQMOD. You would need to ask its maintainers as to why it is that way. As far as I'm aware, the GSS driver doesn't have this issue; at least it doesn't complain about it. Yes, the "No Sync" switch is primarily for people who use the TheSkyX to drive their mount while using T-Point. This mainly pertains to Software Bisque mount users. Syncs can adulterate the T-Point model. There is a switch in the TSX ASCOM driver to blackhole any syncs that come into it, but the user who originally requested that NINA have a way to not send syncs refused to use that for whatever reason.