A default polynomial approximation is applied to the data
The user is shown the data and the approximation in the VIEW window
The user is shown a dialogue box in which they can accept the default approximation or use a series of checkboxes to add further coefficients
If they accept the default approximation the dialogue box is closed and the script continues. If they select one or more additional checkboxes and press an update button, the script updates the approximation with the additional coefficients and replots the results. This continues until they accept the approximation.
This could be done relatively easily with a dialogue box in a loop, but I'm wondering if there's a way in which the box can stay visible during updates and close when they accept the approximation. This would mean that pressing the update button would allow the script to receive the values of the dialogue box variables and continue the loop. I am familiar with using the OK button to close a dialogue box and let the script receive the variables, but I don't know how to do this just using the EventClick event, if that is the right way to go about this.