Fl_Check_Button* o = new Fl_Check_Button(470, 60 + 15 * numbuttons, 1000, 15, name.c_str());

    Here Fl_Check_Button's constructor is saving the pointer to name.c_str()
    and is not making a copy of the string. So the string has gone out of scope by the
    time the strings are being drawn.

    Instead use:

Fl_Check_Button* o = new Fl_Check_Button(470, 60 + 15 * numbuttons, 1000, 15);
        o->copy_label(name.c_str());