Oh....he was balancing on top of the gate and I quickly took him off and put him on the floor outside the gate (the gate is covered on both sides so they can't see through it). He did not have time to "locate" her position in the room as he was looking how not to fall and where to jump to. I was standing right next to the gate folding clothes on my side of the bed - within a foot of the gate. It happened very, very quickly.

As long as the baby gate is covered - she cannot see the bars to get through and she doesn't try. It's very funny actually. You can watch her - when the gate is not covered, she keeps her eyes on it watching to see who or which cat will come to the gate. When you cover the gate, she completely relaxes and no longer watches the gate - like it's a closed door. I guess what she can't "see" she won't try to get through. At least, that has been what is happening here. Very strange.....

The only "problem" with putting Lexi in the computer room is that the only time she has human companionship is when we are sleeping at night. She sleeps with us. She is fine on her own during the day and we can bring her in the computer room with us when we are in here but it gets very, very hot and stuffy in this room with the door closed with the computers going. We humans can't take the heat!!!

However, Lexi HAS now discovered how to jump up on top of the small upright freezer we have in here (another item throwing heat) and then climb up into the staggered, pillowed closet shelving to nap or whatever on. She "found" my "bread basket" on the shelf of the bookcase in here and well..... it's a cat basket now, not where I can keep my bread. Seems to be her new "favorite spot". I'll see if I can get a picture..... I'm sure she'll be up there at some point today.

(the room is a 10x12)
Sparky IS settling down some. He's in here right now - looking out the window next to Neil's computer. He has been calmer since he has not "seen" her so I think we can still make this work. He was only jumping the gate to get to her food AGAIN!!!

Not to get to HER. He has not even "thought" of her as far as I can see from the way he's been acting. He's a little "food hound" and he really needs to lose some weight.....

When we are passing through the gate (the walk through kind) he might slip in if he's quick; he goes straight for the food bowls. Doesn't even TRY to find where she is. It seems he couldn't care less as long as he can get to the food.

I have been keeping them from seeing each other to make certain that things are all COMPLETELY calm and settled before the very limited viewings start. I just want to be SURE they are both in a "good place" before I start doing that. That's why I'm letting it sit like this for a while. Want to make absolutley certain I am working from square one.
Regarding a cat flap in a window, you can cut a board the width of the window and a little more than the height of the purchased cat flap. Then shut the window and screen on top of the board. Use some sort of hardware gizmo the affix the board to the window- some sort of rectangle thingy where one end gets screwed to the board, and the top to the window.
OH! I SEE!!! Like the "old fashioned" fans you can fit in a window then close the window down on top of them!!!! I got it. Great idea!!! I will certainly see about what I need to create/build some.