The downloaded zip contains another zip file of the same name with all the patches and samples in it. So you need to unzip that before you start.
Hopefully, this should get you on your way.
1/. Click on the Load/Save icon
2/. Select ‘Load’
3/. Navigate to wherever the ‘Fabian Siethoff – NIUE’ extracted folder is on your pc.
4/. Look in the Instruments folder and from there you will find the patches.