First of all, please consider that the X and Pro are two different products and converting from one to another would have no effect to the problem that you are experiencing.
Please kindly follow the steps below to troubleshoot the issue:
- As you already have the Pro theme installed please go o Pro > Settings and click on the Clear Style Cache button.
- If you're using a CDN, please clear the CDN's cache and disable optimization services.
- Test for a plugin conflict. You can do this by deactivating all third-party plugins, and see if the problem remains. If it's fixed, you'll know a plugin caused the problem, and you can narrow down which one by reactivating them one at a time.
- Reset your htaccess file by renaming it to
.htaccess-bak. Then in WP Admin Menu, go to Settings > Permalinks and just click the Save Changes button.
- Increase the PHP Memory Limit of your server. Click here for more detailed information and how to increase the PHP memory limit.
If you still have problems kindly get back to us with the result of the steps above and URL/User/Pass of your WordPress dashboard using the Secure Note functionality of the post to follow up the case.
Also, please name the exact page and the elements that you see it missing and give us details about those elements so that we can identify the problem.