Xbox1, mods enabled, no mods that are stated to affect any questlines.
At the point where you begin building the signal interceptor you speak to your engineer (in my case, Ingram) and are given the recipe for the Stabilized Reflector platform.
Cleared out entire boston airport settlement area, made sure that I had plenty of materials in the workshop, and got to work.
When I build the platform the quest journal does NOT update. Special building items do NOT update. Speaking to Ingram does NOT yield new dialogue. Building several large generators and wiring them to a nearby pylon provides power to the platform, but does NOT update the journal and does NOT yield new dialogue from Ingram.
Ingram gives idle dialogue.
Waiting in a chair or quick traveling doesn't cause ingram to wake up.
Tried reloading earlier save from when I brought the chip to Virgil (losing more than an hour of progress.) Chose the brotherhood again and the same problem presents itself.
Quest marker remains on Workshop, whether I access the building menu from the workshop or by holding down the controller shortcut.
Quest journal still says "build the stabilized reactor platform."
have played beyond this point with brotherhood and with minutemen previously.