footer is wrong and signature verification is wrong

Trying to root my nexus player i have got this. I am in stock recovery trying to rescue my system taking "apply update from ADB" but this not works:

I have tried downloading first the recovery images from nexus player (LMY47V), opening file and extracting the .img file (image-fugu-lmy47v.zip in this case) and runing "adb sideload image-fugu-lmy47v.zip" but the system answer is:

Verifying updatye package....
E:footer is wrong
E:signature verification failed
Instalation aborted

Above that message system say:

Android system recovery <3e>
LMY47V

And i think that .img must work..., but i have tried make the same with all the nexus player images. And with all have the same answer.