Skwire, thanks for your excellent program, I can see many uses.
I have some suggestions that would make it even more useful for me.
1. Don't clear the filter match field when you turn off filter mode - I often want to use it again.
2. A method to import a CSV file, use its first line as header names and delete that row in one operation.
3. More filter types like "doesn't equal", "doesn't contain", "greater than", "less than", regular expression match.