The current LFSDK COM versions return an object array when asking for values from a multi-valued field.

In the past, this object used to return a length of zero if there were no actual data in any of the items in the array.

It now returns 1 as the array length, but when you try to access array object [0] (in C#), it is actually a NULL. 

This is deceptive.  I suggest that if there is NO data in the multi-valued field, querying the array length should return zero, not one.

Many of the applications I have written worked fine in the past, but had to be modified to ignore the fact that the SDK is "lying" that there is a value in the collection, when there is actually none.

As in:

entryFieldData = (LFFieldData) entryDoc.FieldData;

object[] objMultiVals = (object[]) entryFieldData.get_Field(tokenMultiValueFieldName);

if (objMultiVals.Length != 0) 

{

  // Process values here  -- Fails if you try to access objMultiVals[0] -- because it is null.

}