Version 6.67 is a bug-fix release.
There was a bug in v6.65 of Ferret, in computing the definite integral computation, that is using @DIN transform, when doing multi-dimensional integrals in longitude and depth, at a single latitude. This is fixed. This was for the multi-dimensional integral only, and occured when not integrating over latitude. (The bug was not present prior to V6.6.5)
The labels on horizontal color bars and vertical color bars was inconsistent. This is fixed.
NOTE: The 64-bit executable is built on a linux RedHat5 machine. It links with more shared-object libraries than in the past. If you see error message upon trying to install or run Ferret, you may be able to resolve them by getting the appropriate rpm for your operating system.