Customized webport progress bar text

Hi,
 
I’m not sure if what I’d like to do is possible with the webport (via a customised webport), so I thought I’d ask here for advice.
 
While the webport is running you get a progress bar. I’ve previously customised the text on a customized webport instance to display a static message via editing the main.htm file of the webport (
custom message here
), but I’d like to go further and make this dynamic.
Specifically I’d like to be able to display an estimate of how much longer the job has to run. Using various parameters in the running job I can calculate the estimated run time at the start of the job, but I don’t know how (or if) it’s possible to extract and use this with the progress bar.
 
The main.htm file contains the code
 

                                               

                                               

                                                               

                                               

                                               

                                               

                               

 
 
The "activeJobStatusDiv" and “elapsedTimeDiv” are dynamic in that it displays information about what the job is doing as its running (for example searching using Direct enabled DBs or running a sub protocol). This suggests to me that if I could somehow read in information about the estimate run time – for example from a text file, then it should be possible to display this in the “activeJobStatusDiv” or similar.
 
Does anyone know how I can do this (or its possible / supported). It looks like the webportmain.js is calling further functions to do this, but at this point the trail goes cold for me.
 
Thanks