From the toolbar...
View > Add View > Add Library View
This will launch the 'add view' tool. The view you're looking for should be in the list of thumbnails presented there, so long as...
If the customised view you are trying to apply is a view for video files, it will not be present in the list if you are trying to add it to the audio branch of the tree.
The .jvi file itself needs to be in a sub folder of your library folder. If it's not, you need to move it there...
By default, your library will be at:
C:\Users\Leiph\AppData\Roaming\J River\Media Center 25\Library
In there, you should find a folder called "Saved Views". If not, create it yourself, then move your jvi file inside the saved views folder. Now, when you launch the 'Add View' tool, you should see the view you wish to import.
-marko.