> After turn on the controller and connect to kstars, the mount already
> unparked, I do not have to press unpark.

I don't use Park/Unpark since I don't have an observatory, so I am not sure
if what you describe has always been the case for OnStep, or something new
in OnStepX

> The position always set to NCP (though the scope is parking horizontally).

This tells me that something is not right.
Ask in the OnStep mailing list if this is how things are supposed to work or
there is an issue somewhere (whether a bug in the firmware, or the steps
of your workflow).

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