Is this your website https://hopeperformingartscentre.com.au/ ? It shows the theme is already activated here.
You can login to your account. Go to My Account and under Products, you can download it again.
Let us know.
Is it your previous website midwestcentertherapy.com ? We don’t see any flickering issue associated to it, or if it is another one please locate it by sharing us your website url.
We don’t see any issues with our demo themes you mentioned above. We’ve tested with different sytems and browsers.
Could you also cross check if the issue is prevalant if you use other devices apart from yours?