I just finished importing tags from a text file. In my particular case, I had far more lines in my text files than I did mp3 files. (I can explain the reason if anyone's actually interested, but I won't now).
What otherwise would have been an enjoyable experience was a usability nightmare, as mp3tag presented me with a dialog box asking if I wanted to continue each time it encountered a line in the text file that didn't have a corresponding mp3. The choices were YES, NO, and CANCEL.
As one import that I performed had 70 mp3s but approximately 850 lines in the text file, this was a painful process of holding down the 'Y' key (for yes) for perhaps 10 minutes to get mp3tag to continue through the import process each time it presented the dialog box.
My suggestion is that in addition to the option 'Yes', why not provide a button that says 'Yes to All'? This way, only one dialog is presented to the user and if they choose 'yes to all', then the import proceeds unimpeded, matching mp3s to lines in the text file, as best it can.
What do you think?