There is a bug when selecting a value from the given list in an entry link field with multi select enabled. In most cases the selected value does not get taken the first time and you have to redo the selection over and over again till success. Sometimes it takes up to 4-5 times before it works.
Annoying is the fact that you cannot filter the list that shows up in that selection. e.g. sorted on the lastname. The selection list keeps the order in which the rows were added.
Also, the selection list shows unnamed entries for empty entries