Yes, you could do that. You might make the title of the thread more descriptive (what tunes? whose tunes? etc.)

I prefer to see tunes in abc format. You can use a program such as ABCMus to play the abc file and also make a midi file.

To post on Mudcat you could just post the abc with the following statement:
Copy the abc file and paste into Concertina.net, then click on 'convert' to get a score and a midi file.

I use Noteworthy Composer to write the score and then convert it into an abc file with abc2nwc, but it's not hard to write an abc file directly.

Anyway, I always am interested in new tunes.

Cheers, S. in Seattle