You can open projects made in an older version with a newer version of the editor, but not the other way around. So you can download that 4.4.3 project and open it in 4.5 without a problem.
You can open projects made in an older version with a newer version of the editor, but not the other way around. So you can download that 4.4.3 project and open it in 4.5 without a problem.