Broken SCNBoxes after export to dae

I made scene: part is defined in a .scn file, bunch of boxes are added progamatically. But after export to .dae, generated boxes are broken: each side has only one triangle, half of side is empty. Also it's impossible to import this file to Blender. Blender quits. Any ideas?

Broken SCNBoxes after export to dae
 
 
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