Due to the Fortran-like(?) file format; loading a flout file would take ages using functions like textscan or fscanf in Matlab. Therefore using compiled C++ code the file is first converted to a txt file and then the header and data of the fiout file are quickly read into Matlab using the fscanf function.
Code assumes a predefined specific format for the FIOUT file; if it does not work for your files; have a look at the included *.cpp file; it should be easy to edit/improve this.
Thanks to Paul Groot, Academic Medical Center, Amsterdam for the C++ tips.