See Admin guide for instructions to join the relevant file parts together.

The location of map and terrain files:

If you are using an FTP client:
outgoing/releases/Focus/vaisala-map-data

If you are using a web browser (not recommended for these large files)
https://ftp.sigmet.com/files/releases/Focus/vaisala-map-data/

File versions to use:
IRIS Focus versions 5.0, 5.0.1, 5.1.0, 5.1.1, 5.2.0, 5.3.0, 6.0, 7.0, 7.1 :     use vaisala-iris-maps-v2 & vaisala-iris-terrain-v2