PGPLOT is Starlink supported software and bugs should be reported through the usual channels and not by contacting Dr Pearson directly. Problems with the GKS specific code will be dealt with by Starlink but all changes to the code which is common to the two versions of PGPLOT must be made in collaboration with Dr Pearson.
The mixing of calls to PGPLOT and GKS routines is not supported except as described in section 3.4, and neither version supports the calling of GRPCKG routines directly. Existing programs that call GRPCKG should be re-written to call the equivalent PGPLOT routines.