Convert Filename - Tag

Hi,
what am I doing wrong here?
My file names look like this:
01.-Pink-Try.ogg
where Pink is the Artist and Try is the Title and 01. is the track number.
So I figured I might use Convert Filename - Tag to save some manual work here.
But Preview and OK buttons in the Convert options window are greyed out, no matter what I specify as conversion format.
What am I doing wrong here?
Any help is most appreciated.
Thank you,
Steffen

Unfortunately, you do not give even one example of what you have entered.

Here is my suggestion for the example you gave tor a filename:
%track%.-%artist%-%title%

This mask will not work for any filename that has a different pattern.