That seemed to do it. Thanks for the help. In the mean time, I did listen to several videos, then go try a few things out, then close Dorico and listen to some more videos. So I made a little progress.
My next project was to make a little cheat sheet. Then I thought “SOMEONE HAS ALREADY DONE THIS. DO NOT RE-INVENT THE WHEEL!” so I’ll ask you instead. OOOPPPS! See Below!
I’ve seen a keyboard layout in one of the help documents showing the various key combinations. The visual picture is useful. I there also a tabular listing (perhaps by mode) showing the various key combinations? I was going to make a spreadsheet like
Write Mode
ALT + CTL = note lower
ALT + SHIFT = note higher
SHIFT + Arrow = move note
etc.
Is that also in a manual somewhere, or on this forum? I’ll do it myself if I have to, but if someone else has already done it, I’ll borrow theirs. SORRY! I FOUND IT RIGHT BELOW THE KEYBOARD MAPS. MY APOLOGIES! 
One more question for now (I’m sure it’s all in there… I just don’t know the navigation well yet.) Say I have entered 5 bars of notes, and I see that I left out one note. I don’t want to change an existing note. I want to insert, say, a quarter note at beat 4 of measure 2, which will move all the notes over 1 beat, so old note beat 4 of m2 is now beat 1 of m3, etc. I tried several things and all I could get it to do was REPLACE the note.
I"ll keep watching videos. And playing around. THanks for your help. I REALLY want to love this program!