Sorry to be a pain but...
I downloaded the proper installer for BD4 with the msi and ran that to uninstall the version I had.
I then ran it again and installed BD 4.
I then downloaded bd_update_2006_09_13.zip and extracted everything in that to a folder called 'stuff'.
I then selected everything inside 'stuff' copied it and pasted into C:\Program Files\Book Designer 4.0
I fired up BD from my programs menu, dialog popped up to same update found and BD opened with FirstbookEng in the window.
All seems fine except there now isn't an option to make a Reader ebook. So do I have the wrong update, or have I stuffed up somewhere else