Historical first-launch guidance records the following messages before the TOY and NVRAM state files have been initialized. The current 5.1.0 validation did not reproduce this exact first-launch transcript; preserve the console output and configuration if a different diagnostic appears.

ERROR: ISA table corrupt!
Initializing table to defaults
type >>>init to use these changes
 
TIMER_TPS environment variable invalid
Defaulting to 1mS per tick

A controlled EXIT from the console has been validated to save NVRAM boot variables to the configured .nvr file.  Avanti writes the configured .toy file during the orderly state-save path only after the guest has initialized or changed the emulated clock. A later launch using retained state files normally restores the state that was actually saved. Do not treat recurrence of either message as harmless without checking that the configured paths are writable and retained.