Hi Beulah,
No, the second cell of 24dn must have only one digit in it, as 30ac has only three single digits in its three cells. As 33ac has six digits but only three cells, it’s first cell must be 1X, so the answer to 24dn must have the form X11X, and the first cell of 30ac is therefore 1.
This was quite straightforward though I spent some time setting up all the clues on a spreadsheet so that the answers would be calculate automatically as the values of the letters were determined. Like others, I started by getting: A, T and S from 29dn and 30ac and R from 21ac.