Just to add, the patch only fixes this problem in the following conditions:
- The computer running SQL Compare is using a 64-bit edition of Windows
- One or more of the servers being compared are SQL Server 2005 or higher
- The Decrypt encryped objects on SQL 2005 and 2008 databases option is selected
The patch fixes a problem with offset alignment on 64-bit systems -- the program uses pointers to data pages that are only 32-bit friendly and this is what causes the pointer to go out-of-bounds.
There are numerous other causes for the error that may not be covered by the patch, for instance, inconsistent metadata in the database.