After upgrade to Dynamics 365, if you try to 'Export As' a solution containing Business Process Flows, a dependency between the Business Process Flow and its entity in the exported solution prevents importing it on to any target CRM 2016 organization.

After upgrading a CRM 2016 org that contains a Business Process Flow introduced by a solution to Dynamics 365, users will be unable to import this solution back in to a CRM 2016 organization if that solution was packaged via the 'Export As' option from the upgraded organization.

This applies to both online and on-premise customers.

In Dynamics 365, Business Process Flows are represented by entities. These entities will get generated for any Business Process Flows that exist on an organization when it is upgraded to Dynamics 365. However, if the Business Process Flows were introduced via a solution, then on upgrade, this solution will not have these generated Business Process Flow entities automatically added to it as part of the upgrade process. In this case, if the user chooses to 'Export As' this solution to 8.1 or 8.0, required dependencies will be missing from the solution that will prevent it from being imported in to a CRM 2016 organization.

Before attempting to 'Export As' such a solution, ensure that for any Business Process Flow that it contains, the corresponding Business Process Flow entity is added to the solution in Dynamics 365. Once this is done, creating a solution package for CRM 2016 via the 'Export As' option in Dynamics 365 will generate a usable solution that can be imported successfully.