1- In the joined example when I force stem down (2) (WRITE) the slur gets forgotten and doesn’t look right.
I have to correct the slur direction in the properties panel manually (3).
2- In ENGRAVE when you select the grace note to force stem down it is the quarter note that gets the command ???
you have to select the stem of the grace note to have the command fulfilled.
3- Please add a toggle stem direction key command (as in Sib…)
thank you
Claude
You’re right that forcing the stem direction of the grace note does not work as expected in Engrave mode; this is due to some shenanigans with properties that we will address in due course. It does, however, work as expected in Write mode.
We probably will not add a command to toggle stem direction, I’m afraid, but you can assign keyboard shortcuts to the existing commands to force stems down or up in the Key Commands page of Preferences.
Daniel, what’s the reason for no stem toggle? May not be the most correct, but would be the speediest way to do some things.
On a similar topic, I get this for a slur between this grace note and normal note:
Not the most elegant slur! 
Maybe this would be something to improve in some update?
Thanks,
Kevin
P.S. I also wouldn’t mind a simple toggle key for some things like stem or tie directions.
If you delve into Engraving Options/Slurs and look for the grace notes, then play with the collision settings, it’s possible to arrive at a near perfect solution for those slurs. I did it once, but don’t recall the exact values 
Thanks Fratveno. If I figure it out, I’ll post the settings.
Our commands for forcing stem direction don’t work as a toggle: you specify whether the stems should be forced up or forced down.
Grace Notes are one of those areas where I’ve fallen into bad habits. Rather than include them as part of ongoing note entry, they’re one of the elements, along with playing techniques, text etc., that I used to go back and add to the score later on (something Ive been doing for years). I’m now forcing myself to include them as part of note entry in Dorico as it’s less work.
The reason I mention it is that it occurred to me a month or so ago that I don’t think I’ve ever seen a grace note that wasn’t slurred. I’m sure they exist, but I can’t recall seeing them. I found myself wondering whether, if the slurs really are that widespread, Grace Notes shouldn’t automatically be slurred - with the obvious option of deleting the slur later, if necessary.
David Tee, slurs started to be added to small notes like grace notes and appoggiaturas in the middle of the 19th century. Before then, slurs were not used because such notes were always slurred by default. Then came an age when everything was written out, including unnecessary things like slurs for grace notes. Music being such a conservative art form, we are still using these unnecessary slurs for grace notes as the standard. You will rarely see them omitted in the concert music with the exception of authentic editions of 17th-19th century music that present the text exactly as it was notated by the composer and the original publisher. Hopefully, Dorico allows one to turn off the slur for grace notes on a global basis.
There are plenty of slurred grace notes in 18th century manuscripts - a couple of examples attached.
You are absolutely right, Rob. I should have said that the practice of using slurs for all grace notes as a matter of course as at present started in the middle of the 19th century. Before then, it was hit or miss and actually rare for many composers. The fact that these slurs were so often omitted shows that were clearly felt to be unnecessary not only by many composers, but also by publishers. In my opinion, they were generally right to omit them because they can clutter up the score for no good reason.
Examples:
The first edition of the last movement of Mozart’s Sonata K. 457 contains 22 appoggiaturas written as small notes. None have a slur. A quick look through the manuscripts of Mozart’s other piano sonatas shows much the same. He rarely (if ever?) slurs single grace notes, but sometimes will slur larger groups such as slides or turns. The New Mozart Edition adds the “missing” slurs.
Of the many grace notes in the first editions of 32 Beethoven’s Piano Sonatas, the vast majority are not slurred. I found only 4 slurred pairs. Beethoven most often doesn’t slur larger groups like slides, turns or arpeggios written as small notes. A look through a bit of his other music showed the same.
The manuscript of the middle part of Chopin’s Mazurka op. 6 no. 1 contains 56 grace notes. None are slurred. Other works like the Preludes and Etudes do not use slurs for grace notes. For example, the “wrong note” Etude op. 25 no. 5 uses no slurs for its many dissonant grace notes. However, Chopin generally slurred small notes when they were an alternate way of showing a broken chord.
As late as Brahms’ Handel Variations (1861) the composer is not slurring grace and other small groups of notes in his manuscript, which was engraved somewhat faithfully in the first edition and the later Breitkopf Complete Works.
Scarlatti’s copyists slur grace notes far more consistently than Mozart, Beethoven, and Chopin. But Scarlatti was working in isolation from the mainstream. J. S. Bach sometimes slurred small notes and sometimes didn’t; it is possible that this was intentional and indicated the rhythmic position and speed of these notes.