Looks like about 45000 actors, which is quite a lot! I guess you have 4 or 5 thousand movies?
Here are some things you can try to trim it down.
In the xSql settings, find the row for actors.
Turn OFF submatch. You will need to say the whole actor name, but that kind of makes sense for actors anyway.
You can also change the sql query to look like this:
select idActor,strActor from actors where idActor in (select idActor from actorlinkmovie where iOrder<5)
this will only use the 5 leading actors from each movie, instead of all the actors. Some movies will list something like 60 actors that you've probably never heard of.
I would guess that you probably only have about 10 to 20 favourite actors that you would ever ask for by name, and you can always edit your list manually to get it down something a bit more reasonable than 45000.
Another option would be to edit the sql to return only actors that appear in at least 4 of your movies (or something like that) but the sql query is more complicated and I haven't figured it out yet.