In IzPack 5.0.7 we introduced XSD validation of all XML descriptors the compiler processes.
There was a certain probability of missing things in the built-in XSDs, so this feature had been made temporarily optional by the 'validating' option of all compiler approaches (Maven, Ant or shell scripts), but the default has been always validating="true".
Nowadays we can be quite sure the XSDs do not contain major errors. XML validation should be now forced in each case to avoid meaningless reports based on typos in the descriptors.
The 'validating' option will be therefore removed.