Compile for Nios (not NiosII)?

If no one answers your question here, try http://www.niosforum.com or file a service request.

If it turns out you do have to go back to old tools, you can get old versions of Quartus and Nios II development software from ftp://ftp.altera.com/outgoing/release. I see only a couple of things there labeled as Nios rather than Nios II, but maybe early versions of Nios II development software had support for Nios.

Make sure the version of Nios or Nios II development software is paired with the correct version of Quartus. A long time ago the version numbers weren't synchronized between Quartus and other tools, so version n of Quartus might not go with the same version n of the Nios/Nios II software.