Finer points of the IBM emulator

Since my terminal emulator of choice is the one I designed and helped write, which actually looks like a 3487HC (except that some of the status line icons are different), with TN5250J as my second choice, I freely admit to being rather appallingly ignorant of how things work in the emulator IBM provides in ACS.

I find myself in a situation where I'm using the IBM emulator, on a virtual WinDoze 10 box, accessed through a browser-based remote desktop. (It's a big improvement over what I was having to use before it was set up.) And while I've been able to remap "Enter" and "Field Exit" to where they belong (at least to terminal jock used to a 102-key InfoWindow), I find that some of the keys on my keyboard are completely invisible to the emulator. Particularly the ones I normally have mapped as "Insert" "Erase EOF," and "Help."

I found the easily-customized "pop-up keypad," but is there a way I can have that open automatically when the emulator launches?

I also found the button-strip called "keypad," that hangs below the status line, evidently for the convenience of those who don't have physical function keys (potentially useful on a Chromebook, for example). Can that be customized?

Any other ideas for setting up a way to provide availability for the specific keystrokes I can't map to any reasonable physical keys? (I'm bound to discover others.)

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JHHL