Launch the OpenSpirit desktop from the PC (the viewers are INT products and do not work on Linux)
Launch the Data Selector and connect to a project
Go to Tools --> DataBrowser --> 3D Viewer or click on the icon:
When the Coordinate System Selector comes up, click on "Select from Data Source...", select the same project as you selected in the OpenSpirit Data Selector
Answer "Yes" to the "Do you want to use the units from the coordinate system?"; then click on "OK"