hi hinder and weclome
To change chords you can do a couple of things.
firstly, if you have made up a songbook in chordie you can go to you songbook and click on "edit" this takes you to the song in a different format. there you can change the chords and hit save. This will change the chords only in your songbook and not the chordie site.
the other way is to go to the bottom of the page where the song is and click on ..... click on...... hmmmmm ( I forgot what it says) click on something similar to "correct this song" or "make changes"
and another way is to transpose the chords.
In the song to the left there is a drop down widow option that you can transpose songs. i.e. if a song is played with the chords A G C Am B and you choose to transpose the chords by +2 then those chords will become B F D Cm C#
does this answer yer question?
ye get some that are cut out for the job and others just get by from pretending