It can be a bug report but I am not sure about that.
The problem is that it's no control for the options in the volatile search.
For example if I change option "match whole word only" in the find dialog it doesn't change behaviour of the volatile search.
It will be really nice to have them.
Another good idea is to change the normal search (or add an option for it) in such way that when you select something and press "Find Next" or "Find Previous" this text will be added into the search history(!) and "Find Next/Previous" will be executed without displaying find dialog and changing options.
You can find such behaviour in TextPad or in Visual and it can help a lot when you work with many long and complex names.
Unfortunately I really missed it in N++...