Can you tell us what is the full path to the file that you are using?
When applying speed to a file, Shotcut has to reopen the file in a special mode to change the speed. I wonder if the speed feature is not able to open the file for some reason - even though it can be opened without the speed feature. Maybe there are some special characters in the file path that are causing a problem.
I see “crdownload” at the end of other file names. Was this file pulled directly out of the Chrome cache? Chrome may have deleted it by the time the export got to it. Files from the Internet need to be saved or copied to another folder, and not used directly from cache. “crdownload” can also indicate a broken download where the file is not complete, which could also produce export errors.
“.crdownload” means a download is in progress, and the file will be renamed when it is done, but Shotcut does not know this. So, Shotcut is correct; it is invalid since the file ending “.crdownload” is gone now. It is not reasonable to expect Shotcut to work with how every browser handles that for every OS it supports. You should wait until the file is done downloading before using it. Likewise, when exporting from Shotcut, you must wait for the export job to complete successfully before uploading it somewhere.