Laura,
On my computer, your file renders correctly in every quality setting.
When choosing the highest quality, there is an initial delay, while the program calculates what it should render. If your computer is "slow", this may take a minute, maybe more.
So, try again, make yourself some coffee or walk the dog, and then look if the rendering is correct...
Hans
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Hans
Ryzen 7-9700X, 32 GB RAM, 500 GB SSD, 2x 2 TB SSD, Geforce GTX 1060 3 GB
