Compared to the SNMP Collection profile in the Desktop launcher, when you select an MIB file to import into the SNMP Collection profile, you browse from you local files instead of from your hard disk.
To open the SNMP Collection Profile, click the Configuration button in the upper left part of the Desktop window, and then select SNMP Collection Profile from the menu.
SNMP Collection Profile - Open File dialog when loading MIB files
In the MIB Workspace area, click the Load MIB Files button. In the Open File dialog, click the Browse button, and the dialog opens the menu to your local files. Select the required MIB file. The file populates the MIB Workspace.
For further information on configuring the SNMP Collection profile, see SNMP Collection Profile, but note that the user documentation is written based on when you are using the Desktop Launcher.