Hi Lee,
The scenario that you described is a functional testing, but not a load testing and thus cannot be done using LoadComplete. You may consider TestComplete (http://smartbear.com/product/testcomplete/web-module/overview/) to implement it.
The essence of load testing (and this is what LoadComplete does) is to send a web request and wait for the response. These actions have no idea about clicks, message boxes and other stuff. In general, the workflow is like this:
1) User clicks on the button;
2) Some code that prepares request data to be send to the web server is executed within the browser;
3) Web request is sent to the web server <== this is where request load testing recording starts;
4) Obtained request is processed on the web server. This processing may include internal requests to the database server, requests to some third-party (web) services, etc.;
5) Some code that prepares response data to be send from the web server back to the client is executed;
6) Response is sent to the client;
7) Response is received on the client <== this is where request load testing recording stops;
8) Obtained response is processed by the browser. This processing may result in a number of additional requests sent to the same or different web servers. These requests are prepared, processed and recorded using the same process as described in steps 2)-8);
9) After the processing of all requests is completed, the message box is displayed to the user.
As it can be seen from the above workflow, LoadComplete records only the time between steps 3) and 7). Everything that is beyond these steps is out of scope of load testing.
If you are not interested in time spent on the client (in the browser) to process the returned data before the message box is displayed (and, depending on your application, this time may be quite significant), you may try the following:
1) In the recorded traffic find the request that is sent after the button is clicked;
2) In the recorded traffic find the request that was sent the last before the message box was displayed;
3) Create a custom page (https://support.smartbear.com/viewarticle/64872/#CreatingCustomPages) that starts from the request that immediately follows the one identified on step 1) and continues up to the request identified on step 2) inclusively;
4) Execute load test and check the reported load time for the custom page defined on step 3). Note, that the reported time will not include the time spent on the client to process the data before the message box is displayed.
Hope that the above will help...
