VTK Python: disappearing lines in the reslice tool

Hi folks,
I’m writing for pointing out an issue that I’m experiencing with Vtk Python.
I’m working with the “reslice” tool and, as you can see in the image below, the line actors are hidden at the begin.
They only appear when you start dragging.

Another important point I want to highlight here is: this strange behaviour only happens when we are using the VTK Python built from the github source code.
If we are using the one installed through Anaconda, everythings work correctly.
Seems the latter has some extra features which let the reslice tools work properly.
Any idea about this strange behaviour?
Let me know if you need extra details.
Thanks and regards,