upgrades can be made in the last tab of the object editor, titled 'upgrades'. Because you only want it so that you can make the tower, set its name and tool tips, make it only a 1 level upgrade and make sure it doesnt have anything set under any of the 'data - effect' stats.
Then once you have designed the upgrade you can add it to a buildings research in the unit editor. Select the building you want to research it from (the factory) and then add it to the stat 'techtree - researches available'.
Then to make it so your tower can not be made without the research open your tower in the unit editor and add the upgrade to 'techtree - requirements'.
do you have a Building where you can choose a race(or more) that is player owned? (red got one and blue, teal and all the otter players)?
you can do it like this.
1. open Object Editor->then under upgrades.
2. make the research: for exampel take iron plating and copy it.
set data-Effect 1: to none
set stats-levels: to 1
set stats-gold base: to (what research cost in gold)
set stats-lumber base: to (what research cost in Wood)
set stats-time base: to (the time to get the Research 30 is good ;D )
set text-name: to Ice Technogly
set text-tooltip: Get Ice Technogly
set text-tooltip-Extended: to get the Ice Technoglt let you build Ice towers.
Remember to Chance the Icons to somthing Ice'y ;D
now add the Research to the Race Chooser Building (hope you got one)
for that you need to do:
1. go under Units
2. pick your Race Chooser Building and add the Resceach under
Techtree-Rescearches Available:
then find you Ice tower(s) and go to:
Techtree-Requirements: and add the Resceach
Simple steps:
1) Make a research (they are located in "upgrades" category)
2) Go on your building that does the upgrades, and set "Researches Avalaible - "your new upgrade"
3) Go on your tower that requires that research, and in "Techtree - upgrades used" or "Techtree - Requiepments" add your new upgrade
i did that .... but it still is able to be built .. and .. after i upgrade .. the damage of the tower increased by 1 .. even though i set it to availability
Here, I've made the ice tower upgrade for you, you will see it down the bottom of the upgrades list under custom - human. You can change the name and the gold costs to what you want.
All you need to do is add this to the factories 'techtree - researches available' and to the towers 'techtree - requirements' in the unit editor.
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.