Yes, you can update to 0.90 by changing this line in your built.sbt:
Seq("ch.unibas.cs.gravis" %% "scalismo-ui" % "0.90.0")
I updated from 0.18 to 0.90 and everything works very well: the main thing I have to do is to change StatisticalShapeModel to PointDistributionModel as Marcel explained here:
and use the class transformation if you have mesh transformation.
Also load/save .h5 files break and just follow the API-doc to fix them, there is not much work to fix them.