To some people 256 was not enough! We tried to put each component on separate layers but ran out with 256 in some of the larger assemblies we used to do. We even had a GRIP program for adding components that would switch to the next free layer.
Intergraph IDMS had 1024, as did Anvil 5000 and AutoTrol, I think. Of course the legacy of Unigraphics is Hanratty code prior to him writing the Anvil series. Autotrol was also legacy Hanratty code.
"Wildfires are dangerous, hard to control, and economically catastrophic."
Ben Loosli