How to run .fig from another .fig and how to get values from one .fig to second .fig and oposite

Hi,

I have two .figs a and b. How is it possible to run b.fig from a.fig?

After run I need send any values from a.fig for example count of cars into b.fig into two poup menus.

Than I need send data form b.fig back into a.fig.

Main point is that I need use "for" and "if" commands in b.fig in popup menu.

How is it possible to do it.

Thank you a lot of for help