Hi,
The DevTest installation folder is defined as the property {{LISA_HOME}}.
The project root folder is defined as the property {{LISA_RELATIVE_PROJ_ROOT}}.
But in your description, you did not mentioned about these two real paths.
You can or cannot define the relative path for your data based on the information of the real DevTest installaion folder and project root folder.
If you locate your sheet file data to the Data subfoler for project, then you can define as "{{LISA_RELATIVE_PROJ_ROOT}}/Data/<sheet file name>"
Thank you,