Big Finish has gathered all the original cast (sans Gan) for an audio story filling in the rather major gaps between Star One and Aftermath. The trailer is up. They got a reasonable approximate for Zen, but Blake just sounds waaaaay too much older.
http://www.wimp.com/homeroomteacher/
Don't know what you linked to Kevin, but it has nothing to do with Blake's 7...
Ha ha ha. Oops.
http://www.bigfinish.com/releases/v/blake-s-7-warship---cd-and-download-815