Engine doesn't necessarily have a file size limit. It would mainly come down to request timeouts, file size, or other restrictions with your app server configuration.
If you have a larger course, though (1 GB and up), you might want to handle it differently. You could upload/extract the files yourself, and then use the import by manifest method to create the course in Engine.
With that, you basically pass Engine a path to the manifest of the course rather than sending us the whole zip file. Here's a link to that section of the docs: http://rustici-docs.s3.amazonaws.com/engine/2018.1.x/GettingStarted/Importing.html#advanced-import.
Size Limit for Importing Large Courses

Have more questions? Submit a request