Unfortunately it is not possible to import content from a "newer" version of UPK into an "older" version of UPK.
I haven't found a work-around, and you will receive an error message along the lines of "The import file is invalid..." when you try to import on the older release.
Although, I must say that I recently had an issue exporting an odarc file from 11.0 and importing it to 11.1 - I could not get 11.1 to recognise the 11.0 export - I got the same error message.
I had to rely on the client DBA's to backup the UPK schema incase their upgrade from 11.0 to 11.1 was unsuccessful, but luckily everything went smoothly without the need for utilising the 11.0 export. That being said, exports are still important!
Sorry that I cannot assist any further... It seems like your only alternative would be to restore an instance of the 11.0 DB (if you have one), or to re-record/create the content on the 11.0 system again.
Hope that helps.