Entering the supporter code does not change the game in any significant way (it has about the same data profile as selecting the player's speciality), so there is no reason to expect it to be the source of the problem. However, the supporter panel is located in the options menu and there is a bug associated with saving the settings file on some computers which has similar behavior to your problem. If that bug is your problem, then deleting the "settings.ini" file from the appdata folder (located at "%appdata%/Strive" on Windows) will allow your game to start again.
On itch.io, the Bugfix mod V6b includes automatic handling of this bug, though you will still lose your saved settings when it occurs. Otherwise, I recommend getting the Debug mod to get the error messages so that the source of the problem can be identified.