Hi Laila,
Sorry to hear about the troubles.
Can you give the exact warning you’re given when attempting to save the setting after hiding related events?
To change the hover color, check out this article. One other idea would be to open “Inspect” by right-clicking on your mouse. You can identify the CSS classes and make necessary changes wherever you handle your custom CSS.
You can also use “Inspect” to make CSS changes to fix the title issue being too close to the edge. Another route for that would be to do a custom template override as outlined in our Themer’s Guide.
Thanks for posting to the support forums and I hope this information helps. Have a great day 🙂