Originally Posted by AlanY
that's great, it works.
many many thanks
You're welcome, but I got you only part of the way. You'll want to decide whether you want your authors all to appear as LN, FN or FN LN. Then you want to set your tweaks so that the author_sort is set correctly when you bring in new books. (In case you aren't familiar with it, author_sort controls how your authors are sorted) Look in Preferences for the new and improved Tweaks setting screen. You may need to use Search and Replace to fix any errors you have now, but once all that's set, you won't have to use it again.
Feel free to ask if more help is needed.