The Tahoma font issue is not related to QuarkXPress. It is font a version issue.
The version of Tahoma font which comes preinstalled with Mac is 5.012x. It doesn’t support Armenian code page and hence it doesn’t contain Armenian characters. It’s font location is /Library/Fonts/Tahoma.ttf
The version of Tahoma font which comes preinstalled with Windows 10 is 6.91. It supports Armenian code page and it contains Armenian characters.
If you install Microsoft Office 2016 on your system, then it will install Microsoft font on your system (location: /Library/Fonts/Microsoft/Tahoma.ttf). The version of the Tahoma font which installed with Microsoft Office is 5.25i and it supports Armenian code page and it contains Armenian characters.
Option 1: You can remove the default Tahoma (which was preinstalled by mac) and replace it with Microsoft Office Tahoma font. You can do to manually, or use Font Book or any font management utility.
Option 2: Copy the Tahoma font from Windows to Mac. Remove the default Tahoma (which was preinstalled by Mac) and replace it with Windows Tahoma font.
Senior Technical Lead, Quality Assurance
QUARKXPRESS PUBLISHING R&D (INDIA) PVT. LTD.
A-45, Industrial Area, Phase 8-B, Mohali, Punjab, India Pin: 160059 firstname.lastname@example.org