The pre-alpha version of Dread didn't have a name yet. Name of the file that included pre-alpha was called zombiegame.rbxl. It featured a free modeled gun kit, poorly made zombie animations, inefficent ragdoll system and a mesh of a vending machine.
You can download the file here (Mega.nz): zombiegame.rbxl
The alpha version of Dread was solely made for testing purposes. It featured a map that can be found in the free models, a Pistol made from scratch and was set on a Deathmatch gamemode. The only GUI that existed was the health bar and the ammo indicator.
BetaThe beta version of Dread was more serious than the previous versions. It featured 2 maps, 3 zombies, 3 weapons, a much better menu etc. It recieved mostly positive feedback and due to that has led to creation of the Dread wiki and the Dread Discord channel
Dread Legacy was basically Dread Beta Reborn (Dread 0.29+). It featured ROBUX Payments, bug fixes and a new theme song.
The release version of Dread was built from scratch instead of updating the beta version due to gameplay issues and need for being ported over Filtering Enabled. It was officially released on August 25th and gained a lot of success. The game version was skipped from 0.30 to 1.00