If you encounter the issue, that the „last row“ and „last column“ setting is not working in Confluence´s Excel macro, this is a pitty. As to find in the comments of the official bug report (including steps about how to reproduce) at Atlassian (https://jira.atlassian.com/browse/CONF-31741), they won´t fix this issue, because the Excel macro is deprecated.
Since I´m using the macro quite heavily, I´ve played a bit around and found the following workaround that might be also working for you:
- Add your Excel attachment
- Add the Excel macro
- Set last row/ column
- Save the page
- Edit the page
- Add a new version of your Excel attachment
- Save the page
Now the settings in „last row/ column“ are applied correctly.