Isn't that Kaypro Barbara.

I use a capo frequently. The Shubb and the Kaypro seem to do a good job of not putting your strings out of whack. As Barbara said, the old elastic ones are notorious.

Step One: Make sure your strings are in tune before you put the capo on.

Step Two: Hold the capo against the strings as you "tighten it up." This increase the chance of getting even tension across the fret board.

Step Three: Check the tuning. If it is seriously "out of whack", repeat Steps One and Two.

Step Four: Adjust as needed. The problem should not include more than one or two strings. The tension and bend that the capo puts on the strings tends to make them a bit sharp, hopefully in a uniform manner. If one or two are out they tend to be sharper, not flatter.

I have a notoriously tin ear when it comes to tuning. I use a Sabine electronic tuner. It has a capability of setting the pitch outside of A = 440. I find this helpful when a string or two is out due to capoing.

If you tune down, you probably shouldn't go more than one whole step (two notes) with the strings you normally use. If you want to lower the strings more, you will find a heavier gauge will give you more tension for the same note (which is why you shouldn't use heavy gauge at concert pitch which can lead to inadvertant folding of your guitar).

As Chet said, you may have to widen the slots on the nut, but that may not be a problem unless you get extra-heavy strings.

Another option, is to transpose the song into another key. If the guitar work is vital, this may cause problems. However, it also may call upon your creativity and you may end up with a "unique" version of the song.

Good luck with all of this.

Roger in Baltimore