I found these instructions and just wanted to confirm if they are still valid.
I followed the first part — exported a group into a folder on my desktop.
For the import, the instructions state that the contents of the folder should be selected to be added into the new database. However, there is a file (DEVONtech_storage) that is greyed out and cannot be selected. Is that an issue? Should I move this file somewhere? Can I delete it?
That file contains metadata for the exported items. I suggest you include it.
I cannot select that file though because it is grayed out. Where should I move it to?
I suppose if one has multiple databases and each one has a metadata file, it would be a good idea to know which metadata file is for which database. What is a good way to address this?
Just to clarify that I actually see two such files:
Folder on desktop
A. group to be imported
various files from the group to be imported
DEVONtech_storage (grayed out)
B. DEVONtech_storage (grayed out)
To import, I will choose A, but in both cases the metadata file is grayed out.
If you import a Finder folder with a DEVONtech_storage file in it, it will be used in the import.
Thank you! And I hope you do take some weekends off 
Is there a setting I need to turn off for the tags the transfer to the new database?
The indexing finished now for the new database, but I do not see the tags transferred. I have smart folders which are empty in the new database because the files and groups are not tagged.
If in DEVONthink 4, what is set in the Files > Tags > Finder > Import Tags ?
The tags are exported with the documents and should be present when imported.
Did you leave the DEVONtech_storage files in place?
Both Import tags and Export tags are checked in the settings in DT4.
I did not move either of the DEVONtech_storage files. I chose the contents of the folder on my desktop, but this means that the grayed out DEVONtech_storage is not selected.
I thought I am not support to click on the desktop folder for import but to selected everything in the content of that folder.
Did you export everything onto your desktop? If so, did you have nothing else on your desktop?
I exported everything in a folder named ’transfer’ on my desktop. I did not export the files all over the desktop. I have other files on my desktop at the moment, but the exported DT4 files are not mixed with others.
Then select the transfer folder when you use the import command in DEVONthink. It should use the DEVONtech_storage files on import.
I tried several times from scratch exporting the group from the original database onto a designated folder on my desktop and importing that folder into a newly created database. Before exporting the group, I confirmed that Import Tags is selected. Still no success with the tags in the new database. Is there anything else that I might have checked off regarding the tags?
No, there are no other settings for this. Open a support ticket and include a screencast or screen captures showing the tagged documents before export and the sam documents after importing into a new database.
