When I go to "Prepare to Print!", it shows one process as highlighted when it first opens. If I then click on that highlighted process I get a dashed box around the process making it seem like you have selected that process (see screenshot below that looks like I have something selected but really I don't). But if I select OK, it won't really prepare the print (create tool paths) because no selection has really been selected. I have to go back and select the process again from the menu of options (and then it will be highlighted again) and then it will prepare to print when I click "OK".
PSS