[Therion] wall option size

Should we be able to use the options 'size', 'l-size', 'r-size' with wall linetypes? It seems it is not allowed, but I was hoping to be able to invoke a reduced symbol size for a small narrow pit entrance. Perhaps I have misinterpreted the authors intention for this option? .therion.exe: error -- aePit-BiclopsPlan.th2 [14] -- r-size not valid with type wall Thanks Bruce