I know about this warning-message. First time after “cooking failed” I got 4 error and about 1.5k warnings. I decided that warnings make errors and I tried to fix warnings. Now I get 4 errors and 6 warnings. I fixed about 1.5k warnings and I get 4 errors again. I found a lot of posts about Can’t find file '/Script/YourProjectName and no one helped me fix this warning. But…
My experience make me think that possible to ignore warnings and get success cooking. But cooking will fail every time if exists any errors. I think if I fix all warnings I will get 4 errors and “cooking failed” again.
I hope my English doesn’t make you cry )