I need to understand what’s wrong with giving a name to your colors and then grouping tabbles by color name (shortcut ALT+y).
Secondly, I don’t understand what you mean when you say "my files lost the old categories". Did you mean to say "my files lost the old tabbles" or "my tabbles lost the old categories"?
Also, I see that in a previous post you were asking for multi-level categories (i.e. hierarchical categories, i.e. hierarchical groups of tabbles). I would like to see an example of how you would arrange tabbles if you had such a feature.
Also, how many categories did you have? (i.e. how many colors do you now have)