they didbt work in what? Poser supports both formats. 3ds is 3d studio format and dxf is autocad, both are popular formats in 3d modeling

aka MCDLabs
also known as Daniel Merrill a grumpy old disabled Jarhead.
checkout my freebies at
https://www.sharecg.com/pf/full_uploads.php?pf_user_name=mcdlabs