I found this on Khang’s website. Dunno if it helps.
Hook References
bwp_gxs_query_var_non_perma – Used to change the default bwpsitemap query var when pretty permalink is not set. (filter)
bwp_gxs_xslt – Used to define the custom XSLT style sheet’s URL (filter)
bwp_gxs_module_dir – Used to define the custom module folder (filter)
bwp_gxs_module_mapping – Used to map a module to another module, for example you can map post_format to post_tag. This will be explained in more details later. (filter)
bwp_gxs_rewrite_rules – Used to define your own rewrite rules. This should be used when you add a custom sitemapindex. Example above. (filter)
bwp_gxs_post_where – Allows you to filter the ‘where’ part in post modules’ queries. (filter, additional variable: $post_type – the currently requested post_type)
bwp_gxs_term_exclude – Allows you to exclude certain terms for a specific taxonomy. (filter, additional variable: $taxonomy – the currently requested taxonomy)
bwp_gxs_freq – Allows you to use your own algorithm to calculate change frequency. (filter, additional variable: $post object)
bwp_gxs_priority_score – Allows you to use your own algorithm to calculate priority. (filter, additional variables: $post object, $freq – calculated change frequency)
bwp_gxs_news_name – Allows you to set a custom sitename for your news sitemap without having to change the sitename setting inside WordPress (filter).
bwp_gxs_news_keyword_map – Allows you to map your categories in your language to Google News’s suggested categories in English (filter).
bwp_gxs_modules_built – Fire after all default modules are defined. Use this to add or remove modules from the default sitemapindex. (action)