I am having this problem too and as you say it makes Poser 8 unusable. Sometimes it finds textures but more often than not it doesn't.
I have deep search set and have checked the .cr2/pz2 files and all of the paths are relative. Not sure if it has anything to do with it but I am on Vista 64-bit with UAC turned off.

One thing you can do, once you have located all of the textures that Poser 8 can't find, is use the python script 'collectSceneInventory' (Scripts > Utility) to save the scene and all of the textures that it uses in a folder. Next time you can open the scene from there without 'can't find texture' errors. Too much work for me though.

I have now given up with Poser 8 and am sticking with Poser Pro where textures from the same external runtimes load fine. I hope this isn't going to be an issue in Poser Pro 2010?

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