When using "Save As" and "Pack and Go" to create a copy of an assembly for iterative modifications, I noticed that changes made in the copied assembly are syncing back to the original assembly. 

Could you please guide me on how to create a copy of an assembly without syncing changes back to the original files? I want to ensure that modifications made in the copied assembly do not impact the original assembly. 

Thank you

Edu ​​​​​​​