I had an issue where the SDK was trying to drop and re-create a default. The only difference in the defaults was that one of them had a comment above it (a comment was included in the SQL batch when the default was created). I modified our usage of the SDK to include the Options.IgnoreComments setting. However, it still attempted to drop and re-create the default (it still considered the comment as a difference). This works properly in SQL Compare 220.127.116.110, but does not appear to work propertly in the SDK. I tested comparing stored procedures via the SDK where only comments were different, and the SDK correctly chose not to synchronize the stored procedures (I did not test any other object types). I was able to resolve simply by setting the Options.IncludeDependencies so that the SDK can include these erroneous differences and still update the database successfully. However, this still apears to be a bug in the SDK.