there are no skin changes from 2.4.0.0 to 2.4.0.8
mojoportal-2-4-0-8-mysqldatalayer-GPL.zip is only the data layer, if you are using MySql, you would start with
mojoportal-2-4-0-8-mssql-net45-deploymentfiles.zip
extract that locally
then extract the the mysqldata layer and copy the contents of the bin and setup folders into the previously extracted package for mssql to replace the data dlls with the corresponding mysql ones
then extract the patch to replace the mojoPortal.Web.dll
then copy any customizations from your current Web.config file into the new one, machinekey, connectionstring, and any other custom changes you have made
then your local package is ready to deploy