I am getting strange artefacts in an obj file exported from an MoI for use in Kerkythea. Keyshot shows similar problems if I use it to open the obj file. The object is a thin planar with many holes removed with the boolean tools (see attached) and although the holes are fine in MoI they end up squashed or angular after going through the MoI export. Any suggestions as to what I might be doing wrong? The 3dm model is rather large so I'd prefer not to post it here... Ultimately the thin plate with the holes in it is meant to be close to transparent, like a sheet of glass with holes in it.

Thanks
Dan