One of my teachers, who is very interested in the program, has asked me when this will be added since he (and I) use this a lot in piano writing. I know for a fact many people do.
P.D: Apparently the guys from Steinberg Spain are coming to my uni to show us Dorico in a couple of weeks, would it make sense that they come when 1.2 has gone out? 
Laissez vibrer ties will indeed be included in Dorico 1.2, but Iām afraid thereās no change to the handling of three-staff piano music. Somewhere on the forum somebody has posted a template containing a three-staff piano that you can download and use until such time as we have proper support for this (which is definitely coming in the future).
Support for laissez vibrer ties sounds fantastic! Will we be able to customize them so they can be used to fake ties into seconda voltas?
You can edit the shape and position of l.v. ties in Engrave mode like any other tie, so I daresay it will be possible to abuse them in all sorts of creative ways.
This is great news 
Thanks great! How will they behave in play mode? How will it be determined how long the note is extended for? Next pedal change could be an option, but that would work on piano.
Thereās no specific playback behaviour for l.v. ties in this release, Iām afraid: they will play back as if the note were not tied. But you can of course go into Play mode and drag the played duration of the note to any duration you like without affecting the display in the score.
in the expression maps editor, there is a laisser vibrer technique. I tried to assign a length of 200% to ālaisser vibrerā to no awail, in fact more than 100%
does not stick and is always reset to 100%
The l.v. playing technique isnāt yet supported.