If I open my (4.12.2+ModAct) bldconf.ini file:
[builder_plugins]
(builder.PlMapLoad)
(builder.PlMission)
(builder.PlMisAir,sectFile=com/maddox/il2/objects/air.ini)
(builder.PlMisChief,sectFile=com/maddox/il2/objects/chief.ini)
(builder.PlMisStatic,sectFile=com/maddox/il2/objects/stationary.ini)
(builder.PlMisRocket,sectFile=com/maddox/il2/objects/rockets.ini)
(builder.PlMisHouse,sectFile=com/maddox/il2/objects/static.ini)
(builder.PlMisTarget)
(builder.PlMisBrief)
(builder.PlMisBorn)
(builder.PlMisStaticCamera)
(builder.PlMisDestruction)
(builder.PlMisFront)
[builder config]
bShowGrid true
bShowName true
bViewRunaway true
bShowTime true
bShowArmy [3,true,true,true]
iLightLand 255
iconSize 32
bViewBridge true
bAnimateCamera true
bActorOnLand true
bSaveViewHLand true
bShowLandscape true
iLightDestruction 137
iWaterLevel 191
defFullDX 32.0
defFullDY 24.0
And change it to:
[builder_plugins]
(builder.PlMapLoad)
(builder.PlMapActors,sectFile=com/maddox/il2/objects/static.ini)
(builder.PlMapAirdrome)
(builder.PlMapLabel)
(builder.PlMapText)
[builder config]
bShowGrid false
bShowName true
bViewRunaway true
bShowTime true
bShowArmy [3,true,true,true]
iLightLand 255
iconSize 32
bViewBridge true
bAnimateCamera true
bActorOnLand true
bSaveViewHLand true
bShowLandscape true
iLightDestruction 128
iWaterLevel 191
I get the unlocked FMB (or part of) where I can open maps and (potentially) modify stuff. That's as much as I can say because I have never changed a thing. I don't know how to use the unlocked FMB. I think you need to add more files to your game to make it all work.