Elias here with Shopify Support.
Sorry to hear that the Exchange Market App is unable to load the next steps. May I ask which browser you are currently using?
While Shopify is browser friendly to most browsers for the website and admin, we typically recommend using Google Chrome browser as apps are an extension from the admin. Sometimes this involves communicating with third-party servers and may cause some problems for certain browsers. In addition, some apps may have extensions available that are designed for Chrome for added functionality. For reference, here is the guide to our ‘Supported browsers’.
That said, if the issue is happening on Chrome browser, I recommend to try clearing the cache for the browser or try with incognito window. It may also be worth testing on a different device or another browser, like Firefox, so we can isolate the problem between device and browser.
If the problem persists, please get back to me on this thread and I’ll be happy to assist you. It may also be helpful to include any screenshots so that I can take a closer look. -Elias