Currently the standard mapping for Global Address Book solution will some time failed to initial sync and some modification is needed to run it. For example, some mapping will fail to run initial sync with error "Couldn't resolve the guid for the field ", the only solution is to remove the field mentioned in the error message and run the initial sync with the modified mapping, afterward the standard mapping can be run.

Some mapping will fail due to lookup count exceed 10 like Customers V3, CDS Sales order headers, and Vendors V2. The solution again is to modify the mapping by removing some field so the lookup count decrease.

There is more issue with other mapping, but the point is that these mapping need to be working out of the box instead of having to modify them before it can be run.