Bake to layers - layer name restrictions in string creation?

Are there certain restrictions to assign layernames if baking objects?

Using Giulio´s BakeWithAttributes GH will avoid baking objects at all. The Lunchbox component will create the layers, but assigns all objects to the currently selected layer.

I can´t find out why though. Even a substring wont work in this case.

The layernames that do work I created by textpanels and entwine, the other ones with a a vb for creating the date + listlength.