On my MinGW/MSYS/wine platform Fortran 77 example 9 has serious errors (first page almost completely blank, second pagepartially messed up). Fortran 77 example 14a also has serious errors (second page almost completely blank). All these Fortran 77 errors concern contour plots. I do not see these issues on my Linux 64-bit platform.
Arjen has also demonstrated that Fortran 77 results for example 9 and 14a differ from the corresponding C results on his MinGW/MSYS/Windows platform. At the same time Fortran 95 gives perfect results for those examples. I presume his Fortran 77 differences are as bad as mine, but that needs confirmation.
I suspect this is due to my incorporating the flexible-memory routines into the F77 bindings.
I must have missed that example when testing that bit.
Closed as Fortan 77 support has now officially been removed from plplot.