Quarkxpress 21.1.2 - macOs catalina 10.15.7

The QuarkXPress in the App Store may be "free" to download – but the description says that it "is available as a monthly or annual subscription that renews automatically." There's a $28.99 USD Monthly "in-app purchase" – and a $299.99 USD Yearly "in-app purchase"; so maybe not so "free" after all.

The Compatibility section says that it requires macOS 10.13 (i.e., High Sierra) or higher, but the description states that it is compatible with macOS 15.x (Sequoia), macOS 14.x (Sonoma), and macOS 13.x (Ventura).

This makes me wonder if the developer made a mistake when submitting their app to the Mac App Store; that they accidentally told the App Store to check for "10.13 or higher" instead of telling it to check for "13 and higher."

Looks like the OP needs to contact the developer and try to resolve this with them.

How to contact an app developer - Apple Support

If the developer can't or won't fix it, the OP may need to cancel the subscription, and request a refund for the first payment. I would think that the OP would want to mention that they had already contacted the developer and that there was a discrepancy in the Compatibility information in the App Store.

Subscriptions and Billing - Official Apple Support

Request a refund for apps or content that you bought from Apple - Apple Support

Davidcoromina wrote:

What can I do?

For what it's worth, I suspect that the Compatibility information in the App Store is incorrect, that the application is not compatible with anything less than Ventura, and that you will wind up having to ask for your money back.

But still, check with the developer.

it does not look like it Release Notes QXP 21.1

their requirements say

13.x or newer

but there is a free quakrkexpress in app store which seem to run on older macOS versions

QuarkXPress on the Mac App Store

otherwise you can try GIMP it's a free app