I've been starting with USF and trying to duplicate the Soviet tier system. I created a Heavy Armor building, but don't see how to make an icon to build it.
There is an upgrade that Unlocks each tier in USF. These upgrades are in the upgrade slot and not the spawner slot.
(upgrade\aef\research\captain_dispatched_upgrade_mp, upgrade\aef\research\lieutenant_dispatched_upgrade_mp,
upgrade\aef\research\major_dispatched_upgrade_mp)
Upon upgrade for each of the buildings. It hides the upgrade by requiring itself not to be ugraded and the Spawner officer is revealed in the same slot once the upgrade is met. This may sound confusing but look at it and you may understand. The units inside each building requires the upgrade to be researched in order to be used. In order have an additional "tier" (for to call in a Jackson) You could add in another upgrade to T3 for additional items. (change the requirement for the Jackson to this new upgrade)
If you want to build a new tier structure, you will need to add it under Squad_Engineers of the Rear Echelons. If you want your base to build it, you could having a building use an ability for a spawn entity.
Note Display and "Usage and Display" in the requirements will hide it if the requirements are not met.
Also, I tried replacing the M36 in T3 with a M10 but all that happens in the mod is that the M36 disappears. What is the setting to enable new tiers to build? Also, how do I get the M10 to show up in T3? In general, what do I do to change a call-in unit to a buildable unit that is tied to a tier?
Under spawner of the building ebps, this is where you can build your units. The units must have the appropriate requirements met. This might mean, the M10 requires a certain upgrade. Naturally the M10 has requirements for campaign and doctrinal. Remove theses and add a requirement for the upgrade\aef\research\major_dispatched_upgrade_mp.