Hello
I'm playing with the plugin (and translating the doc to French)
I fall on a bug that appears randomly with a drawing (see attachment) depending of the number of streamlines to draw.
Also, if, for a "brand new" polyrectangle no value is given in the Tag property, we get the "Select at least one Stream Polyline Box." alert message, but if the polyrectangle have had a value but the value as been deleted for any reason, we get another message as in attachment.
I'll add the plugin to the plugin Website when translation was finished.
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just for info for the "Group" plugin users:
don't do like me, I didn't understand why I couldn't copy my shape sets to do another test in another location ... and it's just that you have to erase the numeric value first in the "Tag" property of the polyrectangle before making the copy, otherwise the 2 polyrectangles are "grouped" and we cannot move them separately ... oops !!

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David