Warn on forbidden characters in layer names
This cost me at least two weeks and a bunch of gray hair: AutoCAD fails to import DXF files without any kind of warning or debugable info, if there is any of < > / \ “ : ; ? * | = ‘ . in the layer name. To prevent others from the pain I had it might be nice to throw an error on export or at least warn.
Ouch. Sorry you had to deal with that, and thank you for sharing. I don't suppose this is documented in AutoCAD's reference anywhere?
You can find it here: https://knowledge.autodesk.com/support/autocad/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/AutoCAD-Core/files/GUID-CE211679-F264-4128-BE00-BF4E0E7DEA8E-htm.html