If you notice that CORE is running very slow in your browser, you can try logging out of CORE and clearing the cache of your browser. Sometimes that can help resolve browser-related issues.
If you believe the CORE servers are down or if you experience any performance issues, you can report it on Core Community or call Technical Support. As an alternative, you can check the CORE Status site (https://status.bqecore.com) for information about any scheduled maintenance going on or if there are any unexpected issues or outages. You can subscribe to the updates and stay tuned.
Also, note that users who are using a trial version of CORE will be having slower speed compared to the paid/subscribed users because the trial databases are on the trial servers while the subscribed databases have dedicated servers assigned to them.