Hello,
I did try my suggested code in a new RS08 project created by the wizard, and the expected result was obtained without error.
I think your problem is not associated with the ORG NVOPT directive, since this resides at address $3FFC. Your error message actually references address $3FFD, the start of the JMP instruction to the start of the program (for the RS08 it is not a vector). It is this that is probably defined more than once. Did you create the project, in the first instance, using the wizard, and was the RS08 device specified at the outset?
If your difficulties persist, you might consider posting your code, or preferably the complete CW project.
It might be possible that you do not currently have a map file because you have never had a successful compile/link. If you found the PRM file, you should be able to find the map file.
Finally, your previous use of the ABSENTRY directive is not correct.
Regards,
Mac