My CRM problems when importing entities

As I mentioned in the previous post I had problems with the CRM after importing entities. Now I have found the problem, the entity in question had Relation to custom entity in the other CRM that I did not include in the export package. This caused the problem that the attribute from the relation was not found and all the troubles.

So when you export the entities from MS CRM always export all related entities, but at the import phase import only those what you need.