Same error here. I think something has changed with BrickLink that has broken everything. Brick Optimizer and Brickficiency aren't working for me either. As Bricklink has no API it's always going to be a moving target, attempting to scrape the information from HTML directly.
This is why an open source project makes more sense (which is a shame a Brick Wizard showed some promise and had a nice UI). I'm going to see if I can get the Brick Optimizer code to compile and fix whatever is wrong with the Bricklink stuff...