Common reasons why labels won't be coming out the print tool:
1 - When i click print the label just gets displayed in the browser.
This means you don't have the "Print Using Courier IntegrationTool" setting enabled on your user account.
Go Settings -> User Settings
2 - Nothing is happening on the print tool
This could mean that the print tool is logged in as a different username to the other you are printing from. You should only log into the print tool once. If you have multiple pack stations setup, use multiple logins to avoid any mixup!
Check the username you are logged in is the same one using the tool
Can be checked by going Settings -> User Settings
And on the print tool:
3 - Print is printing to the wrong printer.
This will be down to the settings.
In the print tool go to the settings tab and check that the correct prints are selected. Click save and restart the tool.