Hello and welcome.
Quark 9.5.4 officially supports the following:
System requirements: Mac OS X
Software
• Mac OS X® 10.6 (Snow Leopard), Mac OS X 10.7.5 (Lion), Mac OS X 10.8.x (Mountain Lion), Mac OS X 10.9.x (Mavericks)
Hardware
• Mac® Intel® processor
• 2GB RAM or higher
• 2GB hard disk space
Optional
• An Internet connection for activation
• DVD-ROM drive for installation from DVD (not required for installation from download)
This information is from the
QuarkXPress 9.5.4 ReadMe.
Since QuarkXPress 9.5.4 was released back in 2013, there may be issues with later versions of OS X/macOS, especially macOS 10.14.x Mojave, which is 5 macOS versions and 5 years newer.
-Which model Mac?
-Where did you get the QuarkXPress 9.5.4 compatibility information from?
-Have you tried editing/re-adding those images into the document?
C