Hello,
I'm suggesting a bug fix for glyphbtn.cpp.
The setting of the flag 'biDefault' in 'TGlyphButton::SetupWindow' to make the button a default button does not function properly.
The problem is that the complete style (32 bit) is taken for analysis. The better way is to mask the lower part of the style before, like in the functions 'TGlyphButton::BmSetStyle' and 'BButtonProc' in the same file.

original:
void TGlyphButton::SetupWindow()
{
TButton::SetupWindow();

// Update state flags based on current style
//
uint32 style = GetStyle();
if (style & BS_DEFPUSHBUTTON)
Set(biDefault);
if (style & WS_DISABLED)
Set(biDisabled);
...

fix:
void TGlyphButton::SetupWindow()
{
TButton::SetupWindow();

// Update state flags based on current style
//
uint32 style = GetStyle();
uint16 btnStyle = uint16(LoUint16(style) & BUTTONSTYLE_MASK);
if (btnStyle == BS_DEFPUSHBUTTON)
Set(biDefault);
if (style & WS_DISABLED)
Set(biDisabled);
...

Thanks
Jörg