Huh,
I figured out what was the mistake. I had to update templates for a style I choose to be default, too.

You can lock this topic if you want ...

I have installed automod successfully and then "who was here" mod, 1.0.2 version for 3.0.5 phpbb forum version, successfully too. I even have set my mod configuration. Mod can be seen in ACP but not on the board. Forum left the same, just as I didn't do anything.

Have I missed anything?