When clicking on print, then get the first print window and click on print, then the second window does not come up.
If you have checked to make sure Uniprint is installed and open on their computer, and the second screen still does not open then it's the settings.
This is from http://www.churchmanagementsolutions.com/kb/KnowledgebaseArticle50272.aspx?Keywords=uniprint
UniPrint & Mac Common Issues
With remote solutions -Remote Desktop Connection(RDC) the only print driver option is Uni-Print. In order to use Uni-Print you must down load the Uni-Print client for Mac's Uni-Print Mac client download please also see the install instructions Install Instructions.
Some common issues related to Uni-Print on the Mac include:
1) Make sure the Uni-Print client application is open; it should show up on the dock as an active application. There should be a dot below the iconfor UniPrint Client If not go to the applications folder, find it and launch it. Once it is open on the dock, click and hold so that you get a menu, one of the options on this menu is open at Log-in . Select this option so that Uni-Print launches whenever you start your MAC.
3) In Uni-Print preferencesmake sure that the default print action is print directly to printer
If UniPrint will not print correctly, or if just prints lines on the page then you might need to apply the following tweak to get UniPrint working again.
Open RDC preferences and go to the Printers tab, check the Use a Printer Connected to this Mac checkbox and then close the screen.
Under the File menu choose the Save option to save the connection. After the connection is saved, then go back to RDC>Preferences and choose the Printers tab again. Now uncheck the Use a Printer Connected to the Mac checkbox and go back to the File menu and choose the Save option to save the connection. This should reset the UniPrint printer settings and allow you to print from Remote Solutions again.
If the above fix still doesn't allow you to print from Remote Solutions, you might need to uninstall and reinstall the UniPrint client.
To uninstall the UniPrint client, open the Finder and go to Applications; there you should see a folder called something like: "UniPrint Client 4.1" or something similar to that.
Click on that folder and drag it to your Trash can to delete it, then go to the Remote Solutions Mac Setup Guide for instructions on how to install UniPrint:
Then after installing UniPrint, perform the fix documented above and you should be able to print from Remote Solutions again.
You may also need to reboot your Mac before the fixes will take effect.