rem: t_properties->gamespeed = (gint) data; gnibbles_properties_set_tile_size ((gint) data);
add: gnibbles_properties_set_speed ((gint) data);
context: game_speed_cb (GtkWidget *widget, gpointer data){	if (!pref_dialog)		return;	if (GTK_TOGGLE_BUTTON (widget)->active) {		t_properties->gamespeed = (gint) data;		gnibbles_properties_set_tile_size ((gint) data);	}}