If it's blowing up on just exporting a sphere prop then I'd expect you have found a bug of some kind, I'd go ahead and open a ticket with SM tech support even though they won't get back to you at least until after the weekend.  If you really can't wait for their response you might try reinstalling Poser - it can't be that you're doing something wrong, an application should never crash like that.

http://support.smithmicro.com/cs/smkb.cfg/php.exe/enduser/std_alp.php click "Start a New Incident"

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