Dimensions/distances

I am trying to put multiple windows in the garage. I will set a distance from one window to a reference point (wall). Then, the next window is referenced off the first window. When I change the distance between the two windows, it pushes the first window (which I already dimensioned) back. One step forward, one step back ---> lather, rinse, repeat...

I want to dimension one window and put a 'hold' or 'fix object' on it, but don't see that option. Suggestions?

Have a good day!
Michael

Set the distance from the first window to the wall.
Then click on the second window to select it.
Set the distance from the second window to the first.
Then click on the third window to select it.
Set the distance from the third window to the second . . . etc

It sounds like, based on your description, you never select anything other than that first window.