Question: Change of ImportMatrix in Maple 2016?

For many years I succesfully used the command:

Lambda := ImportMatrix(LambdaFile, delimiter = "", datatype = string);

but for some txt files I now got the following error in Maple 2016:
Error, (in ImportMatrix) cannot interpret file

The same code still runs without problems at all in previous versions of Maple.

The strange thing is that other txt files can be still be imported in Maple 2016 without problems.

I will upload two files:

ULSlx3.txt returns an error message

ULStd3.txt no problems

ULSlx3.txt

ULStd3.txt

complete code:

restart;
with(LinearAlgebra); with(Statistics);
interface(rtablesize = infinity);
with(Typesetting):
interface(typesetting=extended):

LambdaFile := "C:/path/ULSlx3.txt";
Lambda := Matrix(5, 1);

in the whatsnew there is no information on changes with respect to the ImportMatrix command, although there is some (unrelated) information on Importing Data:

Importing Data
By default, the Import command now returns a DataFrame when importing from Excel, CSV, DIF, and TSV file formats, and returns a DataSeries when importing from ODS, SXC, and TSV file formats. Use the output option to specify a different format. For example, Import(origin, output=Matrix).

I have no clue what is wrong with my code and why some text files can be imported as before whereas other files returns an error message.

greetings Harry