Use the Full Res Preview pane of the Preferences dialog box (QuarkXPress/Edit menu) to control how the Full Res Preview XTensions module works.

To control where the application caches high-resolution images for display, either click Application Preferences Folder or click Other Folder and then indicate a different location. To indicate a maximum size for the preview cache folder, enter a value in the Maximum Cache Folder Size field.

In the Display Full Resolution Previews For area:

• When All Full Resolution Previews is selected, all pictures in the project that are set to display at full resolution are displayed at full resolution.
• When Selected Full Resolution Previews is checked, pictures set to display at full resolution will only do so when they are selected.

You may want to turn off Full Resolution Preview if you are experiencing a performance issue that you think might be related to this XTensions module. To turn off Full Resolution Preview when opening a project, check Disable Full Resolution Previews on Open. If Full Resolution Preview has been specified for a picture, the picture retains that setting; however, the picture does not actually display at full resolution unless you enable Full Resolution Preview for the layout by choosing View > Full Res Previews. When Disable Full Resolution Previews on Open is unchecked, pictures that were set to display at full resolution will display at full resolution when the project is opened (if View > Full Res Previews is checked).