Crash in an RTW build immediately after changing the model is an RTW Build defect, not an Altia/Simulink connection defect.

Copy and paste an Altia block and its connected components (to test a model with more than 1 Altia block), create an Altia design for the copied Altia block, do an altiartwsetup and RTW Build, the resulting executable crashes.

To fix the problem, remove grt_main.obj in the grt_rtw directory and rebuild. RTW is not recompiling this file when there are certain kinds of changes to the model, but it should recompile it.