Any idea about NAV to CRM connector?

I looked everywhere trying to find someone who can help me with a little problem I have, then I found group so I take my chances writing here. I hope you can help me or put me in the right direction where I can find a solution. 
I have a problem with the connector of dynamics, currently I have the version of Microsoft Dynamics CRM 2015.1 and Microsoft Dynamics NAV version 2009R2, I did create a map that supposed to replicate the data sheet of NAV customers to CRM accounts but it sends me the following error: Exception occurred in Microsoft Dynamics NAV. Right now I have accomplished the connection between and in this direction, from CRM to NAV; but the goal is to move all customers that already exist from NAV to CRM trough the connector, so it creates the relationship to all the customers between both platforms. Once this relationship is established, all the customers and updates will be made from CRM with another map, created in the connector, that goes from CRM accounts to NAV customers, this map it’s on and working good, but I did create a map that supposed to accomplish the goal but it didn’t work. I have been looking for any kind of information about this maps and the right way to make them but I didn’t get success. 
Did you work with this connector? 
Do you have any idea that what I am doing wrong? 

Thank you in advance. 

Arturo Vazquez