Hi Pritpal,
first of all many thanks for update.
ASAP I will try QApplication:installTranslator and QApplication:removeTranslator
I found some troubles with xxxSpinBox.qth related with Qt versions.
I read 4.8 docs and current online docs, so I don't know exactly when changed.
1) QAbstractSpinBox.qth missing
bool isGroupSeparatorShown () const > Qt 4.8
void setGroupSeparatorShown ( bool shown ) > Qt 4.8
2) QDoubleSpinBox.qth difference
void valueChanged ( const QString & text ) <= Qt 4.8
void textChanged ( const QString & text ) > Qt 4.8
3) QSpinBox.qth difference
void valueChanged ( const QString & text ) <= Qt 4.8
void textChanged ( const QString & text ) > Qt 4.8
Best regards
Luigi