Hi there,
Can you please check if you still have this issue if you switch to the parent theme? Also note the footer widget area is hidden by default on this theme – you need to click the triangle with the + at the bottom to expand it.
If you don’t have this issue with the parent theme active, it means there’s a problem with your child theme. But without knowing exactly what you changed in your child theme, how you’ve enqueued style sheets and scripts in functions.php, and preferably being able to see the issue in action on your site itself, it’s impossible be any more specific than that.
I’m also not able to provide in-depth help with a child theme, as we (Automattic) don’t provide that level of customization support, so your best option here might be to hire a professional developer to help you figure out what’s broken in the child theme.
Regarding searches, are you speaking of the Search widget, or searching directly via a URL query? Both of those are part of Core WordPress, so if that’s not working I’d recommend opening a thread in the general support forum. It’s unlikely that that has anything to do with the theme you’re using, as Illustratr doesn’t have any built-in search functionality of its own.