Has anyone had experience with this situation and could give me some advice or background on the problem?

I saw a course on Canvas Commons that I wanted to look at, and my only option was to download/import it. So, I did--and the Commons course completely replaced the existing course I had been working from. What's more: it is not possible to reverse a course import, so I am going to have to recreate my course as best I can from scratch.

There is also no warning in the resource materials (e.g. How do I import and view a Commons resource in Canvas?) telling you that you will lose your existing course if you import a whole course (rather than a smaller import, like a document or module, etc., all of which are simply added to your course).

1. A warning should be prominently included in the resource materials. 
2. The proper steps for importing an entire course should be added to the community instructions. For example, I presume this would entail creating a blank course shell in which to place the imported course.
3. A warning should be included within the Canvas import tool as well! A popup, for example, with a message like, "Confirm that you intend to replace your course with this import" would have been all I needed. (Surely this can be triggered when you click the box to indicate you want to import the whole course?)
4. Commons participants whose courses cannot be fully previewed without a full download might also consider providing a prominent note of warning. 

I'm new to Canvas, and up until now I'd been impressed and pleased with its superior user interface and design to the Blackboard LMS I was used to. However, this problem seems to be a glaringly bad UX/UI gaffe, much the worse because it could be so easily avoided. At least in Blackboard it took a lot more effort to permanently delete a course!

If the Canvas import tool functionality cannot be changed to allow recovery of the course that's lost this way, Canvas should at least provide warnings--and there are ample places to include them. That said, I don't understand why a copy of the existing course can't be automatically archived to the course files when another course is imported over it. Even this message box I'm typing in right now auto-saves!

Also, why is there no other option for viewing a course from Commons than to import/download it, compromising the user's existing content? Why is it not part of the download/import program that when an entire course is being imported a separate shell or subfolder is automatically created to house it, rather than automatically overlaying the existing course? I would think that automatically wiping out the existing course requires more sophisticated programming than importing the new course as a file. 

I can't be the first person who's accidentally lost an entire course in Canvas, when it is so easy to overwrite one by mistake.

What a bummer. I guess my Canvas honeymoon is over.

Does anyone know of a solution or remedy? Thank you for your time.