I have set my draft settings and then once I could see the prospect list I manually adjusted my Top 30, or so.

If I readjust my draft settings, which will readjust my prospect list, to include one player at a position (1B) that I had originally sought zero prospects, can I then go back to my original settings and get my manually adjusted prospect list, or will I get the list I had before manual adjustment?

Click "Rank" to get the manually adjusted prospect list.  Then leave that window open while you adjust your draft settings.  Once your new draft settings are set, save your manual rankings again.

Change settings re-adjusts your list to reflect those weights.

Weights are targets, tho, too.... you never get exactly that distribution.