The saved games should be compatible; none of the other English patches (for the CD version) changed the file format enough that there was no backward compatibility, at least.
It is possible some fixes may not be retroactive (ie the patch could prevent a bug from happening, but not fix it if it has already occurred in a save), but that depends on the nature of the bug and the fix. The problems I've seen mentioned appear to be more related to the game itself, though, rather than something that could get written into the save folder improperly.
I'd guess it is probably safe to continue, unless/until you run into some serious issue, but if you are not in a hurry to finish, or have other games to play, it would be safer to wait.