Each update, according to front page of game/itchio - is recommended to have a fresh save
This update specifically, almost requires it
Before, The Buggy and crystals, along with 3 logs of wood, the pickaxe freebie, and a few other things - all always "reset" and respawned, You couldn't keep them where you wanted them after reloading.
In 0.0.82, This "bug" is "fixed"
However.
These objects now save and load their location data.... which in an old save, where they were "already spawned" and have never been "saved" - There is zero location data written, to load - thus, they don't.
Your buggy is gone because it didn't technically exist in your save file - and was spawned by the game every time you loaded up, now it'll be spawned by your save file, but your save file doesn't have one of those.
If you start a fresh save, The game will spawn a new save, spawning a buggy and the 4 crystals (maybe 3), and your 3 grips and 3 guards - as well as properly spawned crates, coal, and log (you get 1 coal to start with now, I think., could be wrong)
If you don't start a fresh save, the things that used to "always respawn" - will never exist in your gameplay again.