The reason it failed because when you download the images.zip from your local Jupyter notebook and then upload the zip file in the submission, it is looking for the track where it created in the google colab as checkpoint which it fails to trace if you do the way you did and as far as the google colab being slow issue, this issue was resolved recently by using GPU, or in case if it is still slow, one requires the fallback runtime.
Your images achieved an average structural similarity index of 0.73. At least 0.88 is required to pass.
Detailed list:
structural similarity index for ‘salientcat1.jpg’: 0.72.
structural similarity index for ‘salientcat2.jpg’: 0.74.
structural similarity index for ‘salientcatanddog.jpg’: 0.86.
structural similarity index for ‘salientdog1.jpg’: 0.75.
structural similarity index for ‘salientdog2.jpg’: 0.58.
hello guys i am also stuck here. i tried many times i followed every instrutions that are mansioned here but still cant get it