I have finally realized that I was trying to use esphomatrix as it wasn´t intended to. So following the instructions about using automations works fine. Now, time for petitions 
Would it be possible to show a screen for less than one minute? 15 or 30 seconds would be perfect!
I am having problems with gif animations as pepe59 told you in this post
Was he able to solve it finally? Not moving gifs is weird!
Suggestions? Help? Magic? hahaha
This is mi yaml
ehmtx:
id: rgb8x32
show_clock: 4
show_screen: 6
display8x32: ehmtx_display
time: ehmtx_time
week_start_monday: true
duration: 7
font_id: ehmtx_font
clock_interval: 15 #seconds
on_next_screen:
- homeassistant.event:
event: esphome.next_screen
data_template:
iconname: !lambda "return x.c_str();"
text: !lambda "return y.c_str();"
- homeassistant.event:
event: esphome.next_screen
data_template:
iconname: rainbow_icon
text: "prueba"
icons:
- file: _icons/computer.gif
id: computer_icon
#pingpong: true
duration: 500
- file: _icons/varios.gif
id: varios_icon
#pingpong: true
duration: 500
- file: _icons/house.gif
id: house_icon
#pingpong: true
duration: 500