Unpredicable behaviour after boolean union

 From:  AlexSD (ALEXANDERSD)
10016.3 In reply to 10016.2 
I send you model, Michael.

Im mostly sure what entire model till the bolean operation probably was have some errors/misunderstanding of correct pipeline from my side. But anyway its a bit wierd what boolean was working in one part of the model, but fail in other.

If someone intheresting, feel free to download and test it.