If you changed the poly count your object isnt a morph anymore, morph only happens with object with the same point count (theres a problem with the direction count too). No other file format can accept morphs for Poser, only CR2 files or PPZ files, but Carrara cant create them. Yes you will need to export all those morphs ans reassemble it in Poser, since you changed the UV you will have to use a software to paste the new UV to the base object... thats is the way all Content creator do the job, so theres no easy way. After load all in Pose ryou can export as a PPZ or any other format that your friend can use.

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