And please, do not add patronymics to the middle name field but instead add them as "other last names".
If Abrahamsdotter is added to the middle name field, and you do a search for First Name: Christina and Last Name: Abrahamsdotter she will not be found by WT search since it regards Middle Name: Abrahamsdotter to be equal to a First Name.
Try it for yourself and see how many First Name: Abrahamsdotter there is that will never be found when searching for them with Last Name: Abrahamsdotter (or any other patronymic, which in some cases are what we know of, if we are not sure if a family name was used).