The options are: use Auto White balance in NX (White Balance: Set Colour Temperature: New WB: Calculate automatically) as a first step and adjust from there; use click/drag grey white balancing method (White Balance: Set Grey Point); select the type of light in the scene and adjust colour temperature (for example - White Balance: Set Colour Temperature: New WB: Daylight: Cloudy); take a separate shot with custom white balance and copy in NX white balance from it to the shots taken with UniWB.
The options are: use Auto White balance in NX (White Balance: Set Colour Temperature: New WB: Calculate automatically) as a first step and adjust from there; use click/drag grey white balancing method (White Balance: Set Grey Point); select the type of light in the scene and adjust colour temperature (for example - White Balance: Set Colour Temperature: New WB: Daylight: Cloudy); take a separate shot with custom white balance and copy in NX white balance from it to the shots taken with UniWB.