fix crash using instances dialog of dataform navigator fdo#44816
fix crash using instances dialog of dataform navigator fdo#44816

also silence a valgrind  'Conditional jump or move depends on uninitialised value(s)' where initial state of a checkbox was undefined

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core