Strider Hub build options work because it is just a constructor with unsorted build options. Build options without a specific tab (Economy/Defense/Factory/Special) overflow to the Units tab. So adding simple unit tweaks is easy.
Factories don't have the overflow Units tab, instead they have a tab called Units that implements a special build queue at the bottom. I suppose factories could have an overflow tab for modding, but it would be an untested codepath so I'm not too keen on it. Full mods can override the file that specifies the tab and position of a build option. This doesn't work for tweakunits, so a while ago I added an extra way to specify position.
Tweakunits only touches UnitDefs so I added a customParam for position. It is read here:
https://github.com/ZeroK-RTS/Zero-K/blob/master/LuaUI/Configs/integral_menu_commands_processed.lua#L30Basically, you need to put 'pos_<position name> = <unitdefname>' in custom params. Here is the example from the file.
{factorytank = {
buildoptions = {
[[cloakcon]],
[[spiderscout]],
[[vehraid]],
[[hoverskirm]],
[[jumpblackhole]],
[[gunshipaa]],
[[cloaksnipe]],
[[gunshipheavyskirm]],
[[spidercrabe]],
[[bomberdisarm]],
[[planefighter]],
},
customParams = {
pos_constructor=[[cloakcon]],
pos_raider=[[vehraid]],
pos_weird_raider=[[spiderscout]],
pos_skirmisher=[[hoverskirm]],
pos_riot=[[jumpblackhole]],
pos_anti_air=[[gunshipaa]],
pos_assault=[[cloaksnipe]],
pos_artillery=[[gunshipheavyskirm]],
pos_heavy_something=[[spidercrabe]],
pos_special=[[bomberdisarm]],
pos_utility=[[planefighter]],
}},}
Your next issue will be that the UI only has eleven spots for factory build options. Factories with more twelve or more units is beyond the current capabilities of tweak units.
