Both issues were reported to the A-team by Karl in April with a reminder early in August
I'd not noticed problems with the cursor - only with descenders
Using Beta 2510 19322.20006, I have just checked for cursor position issues using Aptos 11pt in a datasheet but cannot replicate your findings.
So my presumption was that the issues were now both fixed in that build
However I have just discussed this with the Access team.
The issue hasn't been fixed but doesn't appear consistently
Indeed I have now found (and reported) a way of triggering it reliably as follows
Create a form datasheet with Aptos (Detail) 11 pt.
From th Home tab, change it to e.g. 14 pt.
Descenders are displayed correctly. Place the cursor on a letter and select it. Again OK
Using the Home ribbon, revert to 11 pt.
Descenders truncated and the cursor now appears midway between two letters
So for now, I suggest you change the font size to 12pt - the setting will stick for each datasheet
Or change the default font size to 12 pt in Options | Datasheet