The problem is that the source figures are wrong! Bass figures are written with respect to the key.
If you click on your first figure and look in the status bar at the bottom, Dorico understands 2+ to be Cx, not C#. It then assumes that if you want C double sharp, you’re not going to have E and G naturals, too.
All the upper notes of the first chord are ‘in key’: it’s the bass note that is the diminished 7th of VII. Similarly, your third chord is entirely in key, being an A maj 7, so you don’t need a raised 4th. Anyone seeing 642 knows the bass note is a 7th.
If you want ‘actual’ intervals from the bass note, then surely the 4th is augmented, too? (B flat to E natural?) But then you’d also put a sharpened 3 on the bass A, and a raised 4 on the C natural… Where will it end? 
Note that you can type in the names of the chords into the FB popover: VIId7, A7, … and it will give you the right figures!
However, you can achieve the figs you want by changing the Note Input Options for Interpreting Diminished Intervals to “Adjust from Bass Note” (and then re-type 642+). But note that Dorico still thinks you mean a Cx.
I dare say you could make a case for ‘cautionary’ indications of this sort, but at best you’d want something like 2(#), rather than 2+. And Dorico can’t do that yet.