I'm trying to get an unknown upgrade to work - 45 to be specific, although the exact # is irrelevant for my purposes.
What I've done so far:
1) Set the upgrade properties in upgrades.dat (cost, race, max repeats).
2) Set the upgrade dat requirements in firegraft
3) Add the button to a building to research
4) Enable the upgrade behavior through a plugin
However, the button never appears on the building. If I set the condition to "always", the button appears, but clicking on it does nothing. I've tried using unknown upgrade 59 instead of 45, and the same thing happens.
Any ideas, or should I just cannibalize a non-unknown upgrade?
None.