Last night, after we went our for dinner and a beer with Sasha's colleagues, we saw that the Starfish flower cuttings are not doing very well.
Three out of four have light spots on the stem, a symptom of the disease that affected the original plant.
The largest cutting in water clearly shows the dark spots on the roots. I still have some hope for the fourth cutting though, it seems still healthy and I'm glad I placed them in separate pots.

The four cuttings on the window-sill in the living room. Three out of four don't look too good.

The largest cutting in water clearly shows the dark spots that were affecting the original plant.

I still have hope for the fourth cutting. It's the smallest of the 4, but it still looks healthy.