If a corrupt file was written to the saved game folder, deleting the files in the dynamic folder will not help (it can't hurt to try, though).
Different file extensions are associated with different areas of the game;
.0 / .x0 = Aleroth, Ars Magicana, etc
.1 / .x1 = Verdistis, Council Hall
.2 / .x2 = Dark Forest
If the entire fog-of-war is cleared in the Dark Forest, then it may be fixable (see
Revealing maps).
Which quests did you do before entering the castle? I still have my old games, so as long as we both followed a similar path, it may be possible to replace some of the files in your save with corresponding ones from my saves without causing too many other problems. Before going to the castle I had done most of the quests in Rivertown and Verdistis and cleared the Rivertown sewers.
