I just tried a similar construct using a pigment instead of an interior--
thinking that the same error might occur...
#version max (3.5, min (3.8, version));
global_settings { assumed_gamma 1 }
#declare PIG = pigment{bozo}
#declare myPIG = PIG
... but that runs OK! So it seems that the problem might be exclusive to the
'interior' block... or ior... ?
