[DCP-o-matic] XYZ image sequence colour problems

Hi all. I'm trying to make a DCP from a TIFF image sequence. The post house providing the image sequence say that it's XYZ colour space. But when I create a DCP from it, it comes out with a green tinge. I've used colour conversion "none" setting and this is on DCP-o-matic v2.10.5. I don't have access to a projector, so am judging the success (or not) of the conversion using two methods: 1. Viewing in Easy DCP Player demo 2. Converting DCP to ProResHQ Quicktime with ffmeg (ffmpeg -i j2c_...mxf -c:v prores -profile:v 3 output.mov) Here's an example still from the sequence: http://www.cinebox.co/clock.tiff. The clock should be white but instead has a green tinge. I can see 4 possibilities: 1. DCP-o-matic is erroneously introducing a green hue 2. I'm using wrong settings in DCP-o-matic 3. My methods for viewing the resulting DCP aren't colour-accurate 4. The image sequence isn't in fact XYZ Can anyone offer any suggestions? Many thanks, Jim