Ok, to clarify here you are talking about two different things. A) Setting up a token, this is where saving and updating comes into play. B) Using the health bars of a token, this is where the 'no data loss' statement comes into play. Set up the token properly, including setting it as the default token on the character. You can do this from the token settings or from the Character's edit. 1. Set the represents to the NPC character sheet. Set/change name as needed, click the 3 dots to set up who can see the name. 2. Set the values for health, do NOT set the Attribute. Click the 3 dots to set up who can see the bar, numbers, etc. 3. Set the Attribute for other things, like AC. Again, click the 3 dots to set up who can see the bar, numbers, etc. NOTE: if the attribute functions like health, with every token having different values then use the setup for step #2. 4. Update the token to the Character. This can be done on the Token settings or via Use Selected Token on the Character (hit Edit). Note: If editing from the Character rather than the Token then step 4 shouldn't be necessary, but no harm to do it anyhow. 5. Save. 6. Optional: Apply Token Defaults sets up all tokens linked to the character with the new settings. If you have any questions on the specifics of setting tokens feel free to ask.