Unfortunately that registry setting only applies for suggestion listboxes so I have put in a feature request to be able to resize member listboxes as well:
case=76993
The above is a sample code and screenshot how it works when I use "15" for InitialSuggestionBoxHeightInItems.
class resize
{
void resize1() {}
void resize2() {}
void resize3() {}
void resize4() {}
void resize5() {}
void resize6() {}
void resize7() {}
void resize8() {}
void resize9() {}
void resize10() {}
void resize11() {}
void resize12() {}
void resize13() {}
void resize14() {}
void resize15() {}
void resize16() {}
void resize17() {}
void resize18() {}
void resize19() {}
void func()
{
}
};
