Here is a beginning script that does what you want. It should give you a good start on developing a robust script.
Names Default To Here( 1 );
// Find the top directory to get the xlsx files from
path = Pick Directory();
// Read in all of the file names
allFiles = Files In Directory( path, recursive( 1 ) );
// Create a list of just the xlsx files
xlsxFiles = {};
For Each( {file}, allFiles,
If( Word( -1, file, "." ) == "xlsx",
Insert Into( xlsxFiles, file )
)
);
// Open each of the xlsx files one after another
// using the Excel Wizard
For Each( {file, i}, xlsxFiles,
Open( path || xlsxFiles[i], "excel wizard" )
);
Jim