For future reference for anyone who finds this post.
If you are having this problem and creating a WRC file in a subfolder of the project. To make sure the WRC file is in the same units as the Caesar file do the following
- Open the folder with the Caesar files
- find the caesar.cfg file
- copy this caesar.cfg file to the sub folder

Now when you create a WRC calculation in the sub folder, the WRC file will have the same units as the caesar file