The diagnostics software supplied with the ITeX Apollo 2 & 3 based cards is fairly disappointing. It looks 'home made' and provides only the bare minimum amount of information to classify it as a diagnostic tool.
The drivers support a list of service provider networks which may require different VPI/VCI and Encapsulation settings. In most cases, you'll only ever need to use one entry (the BT Wholesale network). If you're lucky enough to have two ADSL lines, one on the BT network and one elsewhere (e.g. Kingston Karoo service) you'll be able to switch profile with ease.
The "Diagnostic" pane provides little useful information other than driver version information. The "Run Diagnostics" button caused the test system to hang for about 10 seconds before displaying a list of tests mainly related to low level communications over your computer's PCI bus. After running the diagnostics check, the ADSL modems (both Apollo 2 and Apollo 3 chipsets) no longer worked until the computer was restarted.