WOW thanks for the verry fast answers :-)
I know that it's like a program.
But I worked up to now with a Magic Lantern Version for the 7d which i needn't install (I lost my cf card - so it's gone:( ). I mean, that I alwas have to klick on "Firmeware Version" and than the magic lantern Software "stars" after a reboot. Do you konw what I mean?
But If you say the new version is quite better than has got hardy bugs, I will Install the new one.

Thanks for your help