This thread is old but Zoythrus never said it was fixed so...
1. Defense buildings with "Attack off" and "Attack on" commands will always (in a working game) fire when attacked.
The difference is:
- The Attack On command will make it fire whenever it sees an oposing unit in attack range.
- The Attack Off command will only attack after it's been attacked at least once. Then it will automatically switch to "Attack on" mode and fire at the attacking foe. There is an option in the XML (which you can see ingame by hovering over the Attack Off button) called "Reaction time". This is the time (see Silnarm's explanation on Glest cycles for infos on how this time is "measured") the defense building will take between being attacked and switching to Attack On mode.
The purpose of the Attack Off mode is to hide your base from being discovered by the enemy. As defense buildings usually have higher sight range than movable units, an enemy foe might go by it without actually seeing you. But if the defense tower attacks that "blind" foe... well, the enemy will then get a good tip on your location, won't it...?

2. In any circumstance, the defense building would aloways attack an enemy unit that had attacked it already unless:
- The attacker has a higher range than that of the defense building (if I remember correctly, the Elf archer, at least on Elves 0.8 would be able to beat the range of a Tech Defense tower). But you said your defense building was being attacked by swordmen so... that's not it in this case.

- The defense building has a very very very high Reaction time, even on Attack On mode (there's one such option for this command too, I believe). But you said you didn't touch the XML's so... (you are talking about Tech, aren't you?)
- The defense tower has a very very very low attack damage value. If smaller than the attacked unit's armor, it will never take a single HP off of it.

A very low attack speed or attack delay value might also make it (look) unusable. Again... XML had to have been changed.
3. Either GAE or MG use their own modified Magitech, it's not the original vanilla Glest Magitech in either case!
I would doubt it was this the cause but...
... When you installed GAE (which BTW never had a 3.2.2 version, that's the last vanilla Glest version number

), did you also install the data package (including the modified Magitech) or just the binaries? Do note the binaries package does include a modified data folder but the tecjs are NOT in there, in no flavour of glest!

Regarding MegaGlest that you're using now... could it be it seems like they're not attacking because of the Reaction times...? But then eventually they do attack...? Could it be it in your current megaglest?
