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I've got a demo version and I used it to work on my assignment, but after staying up for the whole night working on it, I finally realized that I can't save nor export the file. I was wondering if it's possible to save the project I did in the demo version if I buy the professional version later?
thanks ; u ;

You mean to say you worked on something the entire night without ever saving? Otherwise the answer will be, no. It's like asking if you can drive this new car around if you pay for it later.