An easy and quick fix should be:

(In reply to Keno März from comment #8)

While i could not strictly reproduce the bug, I think I found the source.
Calling the convenience method Add(Node data, Node parent) with a null
parent caused the routine to create an invalid parent set that was then
passed on anc could cause a crash later on. If the release flag is set, I
will merge my changes, which I expect to solve the problem.

After your post I tested some more things. As it seems the crash occurs, when I load a binary image segmentation in the .nrrd format. Using a normal grey scale image, all init or reinit functionality works fine using the following Add function of DataStorage:

Update:
The crash already happens on normal toggle to visible and reinit on the loaded data node. The example file includes a minimal plugin with the error. Also the call stack as well as the mitk log are provided.

plugin sorce