There is this item in SDK:Include/include_h/gadgets/layout.h:
#define LAYOUT_LabelColumn (LAYOUT_Dummy+34)
/* (ULONG) LABELTEXT_LEFT or LABELTEXT_RIGHT, the side where object
labels are placed in a vertical group. */
I can't find LABELTEXT_LEFT or LABELTEXT_RIGHT defined anywhere in the SDK. Can someone tell me what the values should be and add them to the SDK?