This suggestions solves customising language specifice messages for Infragistics messages. I was wondering why does Infragistics provide language specifice satellite assemblies. This would save lot of development effort for each client using Infragistics.

I am also looking for best pracices for application specific customisation like Column Header, Add New Box Button Label etc. There is some Microsoft guideline for Localization best practices. Is there something specific for Infragistics.

To be specifice, is there any information as to what properties of controls need to be Localized.

    I think there are a couple of problems with using satellite assemblies. One is that marking properties localizable tends to bloat the size of your assembly. Another is security - there are problems with compiling the controls to use a satellite assembly without the Infragistics StrongNameKey. 

    This is why we use the ResourceCustomizer. To get a list of properties to localize, you can use the link I gave you. It links you to lists of all the localizable strings in all of the Infragistics WinForms assemblies.