Marc -
Is it possible that your system has a Locale other than 'English'?
Numeric values in the simulation file use ‘.’ as the decimal separator, rather than a ‘,’ as is typical in many European locales. The GeoEvent Extension will assume your server’s locale if the Language for Number Formatting parameter is unspecified in the TCP/Text input you've configured to receive the simulated data.
If this is the case, you need to specify en_US for the Language for Number Formatting parameter (see attached illustration).
Module 2 in the Introduction to GeoEvent tutorial was updated July 30th (2015) to clarify this. Please download the latest tutorial and refer to pages 29 - 31 which discusses configuring the TCP/Text input for the exercise.
Hope this information helps -
RJ