1.4.4 added a few hundred bytes worth of data at the end of file (mostly loadout items and some flags such as for… unlocked carts, apparently?), which characters created in Terrasavr from scratch don’t have, much to game’s disappointment.
You can either:
- Create a character in Terraria and then edit it in Terrasavr.
- Use “Rename” button on character select screen in Terraria, which causes the game to re-save the character along with new data.
(as to why the game doesn’t offer to do this automatically, that’ll remain a mystery)
The next update (maybe today or tomorrow - it’s a bunch of work) will have loadouts implemented so that will be gone.