Okay--sorry you're having issues! I'll look this over and figure out the issue ASAP.
Edit: Okay, I just loaded up your save file. I'm able to open and close the Manage Inventory screen, but it looks like a few of the items aren't being parsed correctly, which is probably causing the issue. I'll get right on fixing this; I should hopefully have an update by tomorrow.
Yeah; it looks like it formatted the class requirements attribute for a handful of the items incorrectly. Lines like this...
<CommonInv>Iron Sword||Weapon Hand||c:Swordsman||Fencer||Hero||Champion||||||Sword||23||100||0||0||0||0||0||0||5||0||0||0||0||0||0||0||0||0||0||0||0||0||0||5||||Sword||Ordinary iron sword. Strength +5.</CommonInv>
...should look like this
<CommonInv>Iron Sword||Weapon Hand||c:Swordsman,Fencer,Hero,Champion||||||Sword||23||100||0||0||0||0||0||0||5||0||0||0||0||0||0||0||0||0||0||0||0||0||0||5||||Sword||Ordinary iron sword. Strength +5.</CommonInv>
and this
<Inv>Leather Armor,Torso,c:Swordsman,Fencer,Spearman,Pikeman,Cavalier,Mantis Knight,Hero,Champion,Bandit,Marauder,Crossbowman,Arbalist,Drake,Mentalist,Puppetmaster,Pyrokineticist,Pyrokurios,Cryokineticist,Cryokurios,Skiakineticist,Skiakurios,Photokineticist,Photokurios,,,,0,120,0,0,0,0,0,0,0,0,0,0,5,10,5,0,0,0,0,0,0,0,0,7,,Armor Leather,+5% physical res. (10% vs Slash).||
should be like this:
<Inv>Leather Armor,Torso,c:Swordsman/Fencer/Spearman/Pikeman/Cavalier/Mantis Knight/Hero/Champion/Bandit/Marauder/Crossbowman/Arbalist/Drake/Mentalist/Puppetmaster/Pyrokineticist/Pyrokurios/Cryokineticist/Cryokurios/Skiakineticist/Skiakurios/Photokineticist/Photokurios,,,,0,120,0,0,0,0,0,0,0,0,0,0,5,10,5,0,0,0,0,0,0,0,0,7,,Armor Leather,+5% physical res. (10% vs Slash).||