Engine Error at Building a Carpenters House

release-687 (x64)
…onehearth/components/building/building_component.lua:1143: attempt to index local ‘fab’ (a nil value)
stack traceback:
radiant/modules/common.lua:237: in function 'report_traceback’
radiant/modules/common.lua:248: in function <radiant/modules/common.lua:242>
…onehearth/components/building/building_component.lua:1143: in function ‘can_scaffolding_clear’
…hearth/components/scaffolding/scaffolding_region.lua:373: in function 'instance’
radiant/modules/events.lua:291: in function <radiant/modules/events.lua:285>
[C]: in function 'xpcall’
radiant/modules/common.lua:257: in function 'xpcall’
radiant/modules/events.lua:285: in function ‘trigger’
…earth/components/fabricator/fabricator_component.lua:255: in function 'fn’
radiant/modules/events.lua:288: in function <radiant/modules/events.lua:285>
[C]: in function ‘xpcall’

radiant/controllers/time_tracker_controller.lua:82: in function 'set_now’
radiant/controllers/time_tracker_controller.lua:103: in function 'increment_now’
radiant/modules/timer.lua:13: in function 'instance’
radiant/modules/events.lua:291: in function <radiant/modules/events.lua:285>
[C]: in function 'xpcall’
radiant/modules/common.lua:257: in function 'xpcall’
radiant/modules/events.lua:285: in function 'trigger’
radiant/modules/events.lua:398: in function '_trigger_gameloop’
radiant/modules/events.lua:446: in function '_update’
radiant/server.lua:61: in function <radiant/server.lua:58>

PS: I’m sorry if this is wrong, but this is my first bug report.

PPS: Translated with Google translator from German into English