Oh, that's a bummer. I'll forward a reference to this thread in the original thread.
I used the dopusrt.exe workaround, because DOpus apparently can't directly set the comment metadata to {file} without it (it incorrectly uses the first item for all selected files. The workaround came from this other thread you posted, so I thought this was the solution). Maybe the real problem can be resolved, so the workaround isn't necessary?
In this case here, I don't know if the OP needs to be setting the comment anyway.