v1.4.3 is considered the optimal Smash Hit version to mod since v1.5.0 and greater are poorly developed by another organization.
Necessary Software
Boss rooms
Ticking rooms
Making a menu
Custom text display
A tutorial made by yorshex covering how to use Shatter OSS, a Smash Hit level editor addon for Blender
A tutorial made by yorshex covering Shatter's auto-exporting and stage testing features. It is recommended to read the notes in the description of the video for better understanding