Engrave mode allows pretty good graphical tweaking of all of the elements that Dorico can notate, in terms of fine positioning and adjusting angles, lengths, positions, and so on. It doesn’t yet allow you to manually change note spacing or change the positions of staves, though both of these capabilities will come soon. It also doesn’t allow the free drawing of non-semantic items like lines and curves, etc. So if you’re expecting Engrave mode in Dorico to basically be Adobe Illustrator, you will be disappointed, I’m afraid. However, it does have a lot of powerful capabilities in terms of showing independent pieces of music in different frames at different sizes, superimposing text and graphics, and other clever tricks like that.
It’s important to remember that we are releasing the first ever version of Dorico, and if you look down the list of threads on this forum you will see dozens of other requests concerning guitar notation and chord symbols and playback and user interface changes and goodness knows what else. We plan to address all of these areas over time, but hopefully you can appreciate that the user base for scoring software is exceptionally broad and therefore the functional areas Dorico will be expected to cover are likewise exceptionally broad, and it will take time to get there in all of these areas.