PC died, reinstalled SOMA, all saved progress is gone

[Romulator]

Your save files may be in Steam\userdata\<id>\282140\remote\Main (where <id> are numbers to do with your Steam ID) if they were downloaded with SOMA while reinstalling it.

If so, you may need to move them to (assuming Windows), Documents\My Games\Soma\Main\<user>_<id>\ (where <user> is your steam name and <id> are an arbitrary set of numbers and letters). You may need to start a new game to generate a <user>_<id> folder.

SOMA performs a cloud sync on each run, so you may require to run the game in order to synchronize the saves as well. Should that not work, someone may be able to provide a save file for you at the point you last remember as well, should there not be anything there.