[Plugin: NextGEN Gallery] Need mouseover code to display images

I am looking for someone to write some code that lets me display NextGen images like the ones on this website. https://www.urbanliving360.com/seattle/Escala . When you mouseover a thumbnail, the enlarged version shows up in the larger image at top. I am using the NextGen plug-in at https://cincinnatiurbanliving360.com/downtown-condos-lofts/1125-saint-gregory-cincinnati and this is where I need the code.

Know of anyone who can help me?