This is for Colonization, I would like to get back the old 'arming the gun' sound of Militia when they fortify, this was so cool. Any idea on how to do that?

I don't have colonization, but if it's the same as BTS I think you want to look in Civ4ArtDefines_Units.xml. Some units have a field called ActionSound. I havn't tried it, but it looks like that would be thing to change to get that sound.

Thanks... Tried adding new actions sound (just put an existing script to test the concept) but nothing happened... can it be that units already on map can't be affected dynamically?

I don't have Civ4 on the computer that I'm currently using but my guess would be that if you are loading a saved game after changing the xml value, you won't see a change. If you are starting a game from a WBS file then you would see the change.

Damn, I tried with a new game and no luck either. I don't understand what is going wrong here. Thanks anyway.