Custom reports for Spire are saved on the server in one of 2 places. If the report is required for all companies then save it on the server in C:\Programdata\Spire\Reports
If the report is just for one of the companies then it is saved on the server in C:\Programdata\Spire\Reports\DatabaseName.
The database name can be found by looking at the Spire Tray.
If the custom report is an edited version of one of the stock reports and it has the same file name as the stock one, it will replace the stock one. If it is given a different name then both the stock one and the custom one will appear when the user prints,