Add the KPI object to your sheet and then instead of adding data for your measure type into the function the text you would like to appear on the button in single quotes (ex. 'Sales History'). You can also choose to leave it blank by just entering the two single quotes. Then under number formatting click custom. Then click on the appearance drop down and toggle off show titles in the general drop down and again in the presentation drop down. Then turn on the link to sheet option.
I've used this for linking to internal sheets, HTH