Steve -
You wanted me to let you know how I did .... I DONE GREAT! sooooo ... thank you so very much.
I'm not sure that I did the "error checking" right (I chose to use the @msgbox) but it works like a charm and I'm happy as a pig in (whatever it is that a pig is happy in)

Here's the final On-element-entry programming for the Command Button to "Get The Companion Record."
var Z as int
if Alt ID0 <> "" then
{
globalvalue("vAltId",Alt ID0)
z = @SelectTreeItem("Search Update Menu!Navigation!Save Record")
z = @selecttreeitem("Search Update Menu!Search (F7)")
ID = @globalvalue("vAltId")
z = @selecttreeitem("Search Menu!Search Commands!Retrieve New Results (F10)")
}
else
@msgbox("","There is no Companion Record","")
Also, since I usually prefer to work with my database in search mode with all forms "open," I have another command button to "Return to all Records"
The On-element-entry programming for that Command Button is:
var Z as int
z = @SelectTreeItem("Search Update Menu!Navigation!Save Record")
z = @selecttreeitem("Search Update Menu!Search (F7)")
z = @SelectTreeItem("Search Menu!Clear Form (F3)")
z = @selecttreeitem("Search Menu!Search Commands!Retrieve New Results (F10)")