I've found some issue in console logs, but I don't know when it exactly happens:
Runtime error: [error] Variable <unknown_object>.i_id(101072, -2147483648) not set before reading it. called from vm:field_on_field_set (line 13064) called from game:anon_gml_thread_gml_GlobalScript_GMLive_396240_gml_thread_gml_GlobalScript_GMLive (line 11248) - var l_ar1 = vm_v2_gml_thread_v2_handlers[l_act.__enumIndex__](l__gthis, l_act); called from game:anon_gml_program_gml_GlobalScript_GMLive_120080_gml_program_gml_GlobalScript_GMLive (line 2825) - l_th.i_exec(); called from game:live_call (line 10204) - var l_th = l_pg.i_call_v(l_scriptName, l_vals, false); called from game:obj_event_questionplate_Step_0 (line 3) - if live_call() return live_result; called from obj_event_questionplate:Step_0[L40,c22]
On line 40 in obj_event_questionplate there is:
creator.wait_for = _cutscene;
where "creator" and "_cutscene" are variables with ID of existing objects (_cutscene is just created few lines before).