While customizing the access log fields is permitted the following three must be included:
The custom log format that did not work in Reporter 9 was missing the cs-uri-scheme field. This is the access log format that was causing issues with Reporter 9:
date time c-ip sc-bytes time-taken s-action r-ip sc-status rs-status rs-bytes cs-bytes cs-auth-type cs-username sc-filter-category sc-filter-result cs-method cs-host cs-version sr-bytes cs-uri cs(Referer) rs(Content-Type) cs(User-Agent) cs(Cookie)
The problem was resolved by manually adding cs-uri-scheme to the end of these fields in the access log.
To ensure that all reports work properly, Blue Coat recommends that all required fields, mentioned in this article "What are the required Main HTTP(s) access log fields for optimal performance using Blue Coat Reporter" be in place.