Been trying to track down a really nasty bug for the last couple of days. I added code to give the ability to remove maps from a material. It all works perfect as long as there are still maps defined for the material. Once the number of maps = 0 the extendeddata for that material has to be replaced with new extendeddata. Everything works perfect until the file is saved. During saving there is some rogue pointer overwriting the offset for the material's new extendeddata - this causes the app to think the new extendeddata for the material is located somewhere else when the GR2 file is opened and read thus reading in incorrect data
