DTPO tags

I have been using DTPO now for some time. Defined quite a lot of tags to help me group and organise stuff.
Recently I bought Metatags (from indev.ca) to enable tagged email (Apple mail) Once more the tags are great. However it looks like tags in DTPO and tags in Metatags are separated.

Is there a way to create a tags that can be used in Metatags, DTPO and Finder, in such a way that defined in any of these applications they are usable in the others too?

And yes I understand that items with the same tags but not imported into DTPO will not be found by a DTPO search. It is just that a tag has a meaning for me, and it would be convenient if this would have a system wide presence.

I assume you mean MailTags, but if they have released a new (Metatags) app, then I’m not familiar with it. I have used MailTags in the past, but don’t anymore. If I recall correctly, MailTags supports keywords, labels, and Finder Tags. If you use MailTags’ Finder Tags, those are also compatible with the Finder and DEVONthink. Sorry to say I don’t remember how you enable Finder Tags in MailTags, but the Indev documentation is pretty good-should be easy to find how to do that.

You are right, it is MailTags. The latest version 4. Using latest DTPO on El Capitan (10.11.1)
Finder Tags are enabled.

How are you importing your email into DEVONthink? Also, what happens if you drag a tagged message out of Mail.app, to the Finder-does a Get Info on the message in the Finder indicate that it has tags?

It might also be helpful to contact Indev support, if you haven’t already.