I have a solo-play historical league with three levels of minors. I've simmed 1901 to 1981 (using Lahman). On the Team Stats pages for the minor league teams, under "Team Batting Stats", the first column "Pos" does not indicate the player's position. Instead, a hyphen is showing. It's as if none of the players has been assigned a primary position by the AI. I think this may have an impact on the "Starters" pages for position players: whenever I review "Starters" pages, instead of showing the individual players who started at catcher, 1B, 2B, etc., one player's name will be repeated across all the rows, so that it appears as if one player started in all positions for the entire season. Which is impossible, of course.
I have the detail for all levels set to "Very High Detail".