I worked it out in the end. This may be of use to others
The Blaupunkt saves the favourites in a folder called content\userdata\poi in that folder are 2 files a kix and a kns file. This is what threw me as these files are impenetrable!!
You need to go to the folder - \Save. There you will find a upoi file. Now we are in business using a free download get GPSBabel. This program can convert the upoi file into a KML file. The KML file can be imported to the Pioneer using the NaviExtras program.
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