As I indicated above, dotting a tied note when you have input options set to specify rhythm dots after inputting notes can lead to unexpected results. This is because Dorico sees the quaver tied to a crotchet as a single “note” of 1.5 beats. When you add the dot at the end, Dorico thinks it needs to add half the total value, or an additional 0.75 beats. Why it ends up shortening the tied note (rather than adding a dotted quaver, for example), I’m not entirely sure.
This has been discussed elsewhere on the forum, for example in this post.
For my money, the most predictable and consistent results in Dorico are obtained with both and accidentals/rhythm dots/articulations before pitch. This is not how I was used to working in Finale, and it took a little time to re-train myself, but I’ve been happy with the results.