To all who it might concern.
I just (again) came across a problem in Microsoft Dynamics NAV 2013 R2:
error CS1502: The best overloaded method match for ‘Microsoft.Dynamics.Nav.Runtime.ALStream.ALWrite(Microsoft.Dynamics.Nav.Runtime.INavStreamWriter, Microsoft.Dynamics.Nav.Types.DataError, bool, int)’ has some invalid arguments
Microsoft introduced new variable types (OemText and OemCode) but they did not create new overload functions for stream write/read.
So it is not possible anymore to write/read field content for text or code fields directly into/out of a stream.
The content of the field must be assigned to a text/code variable first before writing it into a stream.
So if anyone of you gets across this issue. This is the solution.