Merge Document Error: Unable to cast object of type 'Aspose.Words.Tables.Table' to type 'Aspose.Words.Paragraph'

I am facing a problem when merging a document into another whenever the document to be merged contains tables, this is the error:
Unable to cast object of type ‘Aspose.Words.Tables.Table’ to type ‘Aspose.Words.Paragraph’.
I have tested by adding images and other objects, that works fine, except if the document has tables.
Actually I am working with version, but I also test the latest version of Aspose Words 6.0.0 and the same result.
I attach a little application where you can reproduce the error.
-What impact should I have if I upgrade my current version with the latest one (6.0.0)?
-Would you recommend me to upgrade it?

I appreciate your help.
Thanks and regards.


Thanks for your request. I modified code of InsertDocumentAtBookamrk and now it should work fine. Please see the attached code.
Best regards.

Hi Alexey,
It works just perfect, thank you very much, I am very happy with your support.
Best regards,