Ok I figured it out. It was the option 'Prevent sites bookmarking themselves' in Options--Filtering that was causing the problem. I mistakenly thought the Filtering options only worked if the Default Filters options were enabled ('Use these filters' and 'Still use popup-related filters').
Would it be too much trouble to see what your custom settings are for Ad Muncher so I can set mine to the same? I figure you would have the optimal settings picked out. I just check things that seem like they are useful and am probably setting Ad Muncher to act too aggressively. I was puzzled as to why no pictures would load on IMDB until I realize the option 'Change referrer field' was causing it. Now I'm not sure what I should or shouldn't check in the Options tab.
Additionally, I think it'd be better if we could also enable/disable individual rows in My Filters instead of only enabling/disabling the whole list.
I'm a temporary user.