When editing these options it would help a lot to show those value(s) already selected in a short list near the top of the dialog above the complete list box of options which FM now presents. It could be a drop-list, provided it showed at least 3 or 4 items w/out clicking - the whole idea is to provide an immediately useful view of existing settings. Also-1: In the same vein, it would be nice if the remaining percentage (to make 100%) were to automatically be assigned to some (settable?) default option, perhaps "uncategorized". This default option would display in the "short list" along with any other percentages the user had applied.
1) Better ease of editing. Click on the short list of existing settings and go straight to the item to edit. Because there are many options and those that one has already set often do not appear in the list box (need to scroll to see them), it is quite fiddly to try to quickly verify or correct settings. Especially because each setting has a percent and potentially the full setting for that property may comprise 3 or more different items with differing value.
2) Much easier to quickly evaluate a multi-value setting when one's able to see them (perhaps sorted by percentage, descending?) display together.
Also-2: Please enable typing in the percentage value directly when an option has been selected by clicking on that line. Ie. eliminate the "change %" button. If there are, at some point in the future, additional values which could be set for that option-line, then a another dialog might be appropriate; but with one settable value, %, the extra click-to-enter just slows down the process. If more space were needed in the dialog, the "Edit" button could be eliminated by a context menu (rt-click) or a secondary dialog could be opened with a dbl-click on the line.
Regards
Rufus
ps. FWIW, I spent a few years designing stuff like this back in prehistoric times, so I can get pretty talkie and opinionated (obviously). Generally speaking it takes 3 or 4 thought iterations before the obviously "right" ways begin to appear. The main problem with a gui is that for each iteration you need a brand new user to actually find out how good the design is - people adapt so quickly, practically immediately, we "get in the groove"; a new noob is needed to quickly stumble and fall into intuitive holes. Which is why I'm immediately barraging you with the things I notice - I won't notice them tomorrow.