it finally didn't crash (under OS3.1's HDToolbox nothing showed up at all!), then my hardfile showed up, partitioned it, formatted, thenOld HDToolbox versions stop enumerating if any device returns error/fails to openIIRC HDToolbox was unable to scan user-defined SCSI devices prior to OS3.5. To configure an RDB hardfile you must scan uaescsi.device but HDToolbox in OS3.1 was hard-coded to scan scsi.device.
Ancient HDToolbox versions only supported scsi.device but at least version that comes with 3.0 works fine. (don't remember which one was first to support it)