I would like some help on how to edi a "guitar pro" tab with tuxguitar. I downloaded the iron maiden bring your daugther tab and there is quite a lot of corrections to do. I understand it was tabbed by ear and it takes a lot of skills.

However the tab was quite off.

How can you add a slide down in the tab ? How can you add extra notes in between two chords ? It won't let me add new things in there.
There's a button at the top of the user interface, below all the flags, which says "1/3". When you have a note selected and you click this it will add a slide to the next note.

To add a note you just click where you want to place it, and type the fret number.
not just that, you also have to have the room. if the tab has 4 chords in a measure, and they are marked as quarter notes, there won't be any room for more notes.
You would have to change the chords to 8ths or 16ths to be able to add in the other notes.