Hi,
You can try TruClient protocol instead as during the execution of the script the browser is used. It is also included Web 2.0 license bundle.
You can use web_js_run() to write a Javascript code to calculate a value which is dynamically generated on the client(browser) side and is expected by the server in the next requestand i.e for values which are not send from the server and which canot be correlated. In such cases it is better to use TruClient protocol.
Kind regards,
Vesela