I have one Numbers file that says "Downloading [the name of the spreadsheet]” every time I open it. Is this going to be a problem?

I have a handful of Numbers spreadsheets that I use routinely. When I open one of them, a small window opens as well; it says "Downloading [the name of the spreadsheet]"...

It never goes away unless I hit the little x at the right of this little window. This is the one and only file that this happens with. What on earth? Is there any risk that the file won't be captured by iCloud or that multiple, inconsistent copies of it will be created?

[Re-Titled by Moderator]