It works fine, except it doesn't display correct progress. I mean, the progress window pops in, but it doesn't display percentage of the overall progress (either in the window or in the taskbar color). Is there any way to fix this?
If you get the new FilterCmd add-in v1.1 which I just updated, you can run this from outside of Opus, and the progress dialog will behave similar to what you'd get from inside of Opus:
The file paths must be full paths, not relative paths or filenames on their own. If they contain spaces, the need "quotes" around them, otherwise quotes are optional.
No, it's redundant, but won't do any harm either. I had copied it from the original command / post without noticing, but have removed it now. (I've left the original post alone, so it's still in that.)