I have an input DCP with has soft open subtitles. Am trying to created a VF DCP which references the picture, sound and subtitles from the OV, and adds closed captions as an additional track, but DCP-o-matic doesn't seem to allow it.

Steps taken:

• Load up the OV DCP.
• Tick "Use as open subtitles" on OV DCP's subtitles track.
• Tick the boxes for "Use this DCP's video/audio/subtitle as OV and make VF" on each of Video, Audio, and Open Subtitles tabs.
• "Add files" to add the closed captions SRT.
• DCP-o-matic comes up with a small window saying "DCP-o-matic had to change your settings for referring to DCPs as OV".
• On the SRT, change setting to "Use as closed captions".
• Return to the OV DCP and try to tick the "Use this DCP's subtitle as OV and make VF" box again.

The box is greyed out - DCP-o-matic blocks referring to OV's subtitles track, because of the added closed captions, it seems.

Is this a bug? Or is it intentional and it's not legal to do this?

I did manage to get around it by closing DCP-o-matic, editing metadata.xml to change ReferenceOpenSubtitle on the OV DCP to 1. When I re-open the project, the box is still greyed out, but is ticked. When I do "Make DCP", DOM happily makes a VF DCP which references the open subtitles, and also adds closed captions track - as I wanted.

So it seems DOM does have the capability to do this, but it's prevented through the GUI. But have I made it do something bad?