Waveform graphs not autoscaling in X

Hello, I have an annoying problem in drawing data with waveform graphs (LV2011).
I will put it in a short statement: I need to compel graphs to properly rescale on the X scale.
Now the details:
I need to show data acquired during a given "event", updating a graph every second. I don't know how long the event will last, but I prefer not to set the X-axis as autoscaled because I don't like the axis rescaling effect. So I initally set the graph as fixed (ScaleFit=0) to a reasonable width in abscissa. When the acquisition ends, I want to show all the data maximized on the available control width, so I set the X axis scaling property to 2. Unfortunately, the graph is often not rescaled. I also tried leaving ScaleFit to 0 and setting the Range:Maximum to the proper value or using the ForceRedraw method, to no avail.
Do you know any trick to compel the X axis to be rescaled?
Paolo
LV 7.0, 7.1, 8.0.1, 2011

No, GerdW, it doesn't work
I tried also with ScaleFit=1 (Autoscale once now) and with more complicated pattern (for example reinit to default, then autoscale, then rewrite data). No success.
In all cases, it mainly works (but not always) when I run the program in the LV environment. The very opposite when I deal with an executable.
Paolo
LV 7.0, 7.1, 8.0.1, 2011

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