Hello, you need to re-organize this. For example, like this:
1) Instead of making the array of a group, use a nested family. Copy to the group to the clipboard, and paste it into a generic model face-based, new family, ungroup it, and place it in a way that relates to a vertical reference plane, like this:

2) Then load the new family into the first family and place it on the strip, anywhere.
3) Create a reference plane some distance to the right of the first vertical reference plane, and create a parameter for Offset. Do the same at the end of the strip, like this:

4) Align and lock the nested arrow to the first offset on the left.
5) In the Family Types window, create new parameters, like this:

6) Select the first arrow, and do Array > Rectangular > Number: 2 > select "Last" from the options bar. Click on the first Offset reference plane, then click on the last Offset reference plane. That will create an array of 2. Now align and lock the last arrow to the Offset reference plane on the right. Now select the array, the line with the number 2, and go to the drop down for parameters and select "# of items.
Now the array is controlled. If you change the Length parameter, the arrows will repeat properly. If necessary, you can change the Offset parameter and/or the Spacing parameter.

Alfredo Medina _________________________________________________________________ ______
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