I have resolved my issues...
I go in advanced setting of media director, click on "view" for device template "Generic PC as MD", and valid "Allowed to modify" in Current Data #233 (+ save page).
In advanded setting i set "LMCE_MD_u0710_i386" in "Model" parameter.
I make a "Rebuilt Image" (maybe it's not necessary), Quick reload and my MD (Fiire Station) start.
But i have another problem. Fiire Station have a Via Unichrome Pro graphic chipset.
I can't start Xserver when "via" is setting in Xorg.conf.
I must set "vesa" to start.
I can't resolved this problem since i use LMCE. I have seen in mantis the same problem and i think that is resolved with 7.10 release.
Last question : When i add a media director, i can choose Fiire Station, but i never can boot with this config. When i boot with Fiire MD, I have red message "Failed Setup_config.sh". Do you have any explain?