Thanks to both responses. In response to rberg, the dsughter window does not always open in the same exact place of size, that is what caused my problem in the first place. I was using screen relative positions for the cursor location. So cursor locations relative to screen or window do not always stay the same. A kluge I am using is to manually move the window as far as possible up and to the left, this seems to be a fixed location on the screen , then I can use screeen relative mouse location, that seems to work since I can position the mother window within the screen with Macro Express. But it is clumsy and requires at least one manual mouse action.
In response to acantor, yes I can navigate on the Filter window with keyboard for some things, not sure if it can work for everything but I will try that out. Of course, it will require initial manual placement of the cursor within the first field of the Filter window. That might work OK.
It is just odd that Macro Express does not seem to reccognize the Filter window and allow cursor movement relative to it. I had hoped there was some way to get it to do that. I've read about "controls", I don't think that will accomplish the goal.
I appreciate the time both of you have taken to assist me, many thanks.