+example, the recognised data is wrong), you should delete the file
+#local-char*#.txt, which contains your local updates. It will then
+only use the centrally provided (and vetted) master file (which is
+automatically updated when you run the PCTB client, by default).
+
+It is also possible to have the OCR system reject particular strings.
+If you put a regexp in #local-reject#.txt, any OCR result which
+matches this string will instead cause an OCR failure, invoking the
+OCR dictionary editor if appropriate. #master-reject#.txt is the
+centrally maintained version of this file.
+
+Alternatively you can edit #local-char15#.txt with a text editor. The
+format is not documented at the moment.
+
+
+Enabling interactive character set update
+-----------------------------------------
+
+Now that you have read this document, you should rerun your OCR job
+with the --edit-charset option. So run
+ ./ypp-commodities --edit-charset
+In future, this option is not usually needed, because it is the
+default if there is a local character set dictionary #local-<h>#.txt
+for the relevant character height.
+
+With --edit-charset, when the OCR finds characters it does not
+understand, it will put up an OCR resolution query window. This will
+display the part of the text it is having trouble with, showing where
+it has got to, and allow you to edit the character set dictionary it
+uses for recognising the text.
+
+The process is subtle and it is important to understand the way the
+machinery works, and the possible mistakes you can make, before
+answering the program. So *Please read this documentation*, which
+explains the meaning of the entries you make.