@ haider512,
I wish I could give you an answer one way or the other, I saw how you links worked on your site.
The iframe worked for my layout.
I did not know how to add the button/tab to my forum layout to get back to the 4images gallery so that is why I decided to go with the iframe.
I would think as long as you are in the same browser window and session, you should be able to bounce back and forth between the two but I have never tried it.
That is why I am planning on looking into this deeper in the future to make it more compatible. When I made this mod, it was to fill the need of my site. I am understanding how the mods work on the smf side better and how to make them so I hope the next version you can have a forum site and a gallery site with links between the two, but that will not be happening very soon,