How to import an ".emx" UML Model saved on version 7.0.5.1 into a 7.0.0 environment

I've been working on some Use Cases, Activity Diagrams and so, using IBM's Rational Software Modeler version 7.0.5.1
The problem is that when I was trying to integrate it into my whole project at office, we have there the 7.0.0 version and I receive a lot of errors when trying to opening the ".emx" file. Editor not supported, and a lot of things.
I have tried exporting the Model to other formats from within 7.0.5.1 but to not succeed. The best I was able to do was creating "fragments" and then importing them into 7.0.0 but all Activity Diagrams are gone and like  trying to create new ones and rearrange everything is a chaos.

I thought it would be like an option to "save as" or "export as" a previous version, like backward compatibility, but it seems not to be one.

Any idea on how can I kind of solve this the easiest way?

I guess some of the problem are all those plug-ins created on the ".metadata" folder of the workspace, but I don't think I can like copy mine and overwrite my office's folder to see if that works.

Obviously when I created the UML Project on my RSM 7.0.5.1 using my RSM 7.0.0 saved model (.emx) it went so fine.
Now that I need to rejoin what I was working on at my office, is that I cannot open my 7.0.5.1 file, not even the .xmi, .um* files of the "export" options given
I am quite afraid I might be loosing everything I worked on the last 3 days, and that's a lot... :S

Thanks in advance