Transported to Lighthouse After Fire And Ice Mission

SpartanSlay3r77 
This is a known issue the team is aware of where after completing the "Fire and Ice" mission, the game returns you to the Lighthouse without triggering the necessary cutscenes, preventing further progression. This issue has been reported by other players, and while there isn't an official fix at the moment, here are some steps you can try to potentially resolve the issue:

1. Save and Reload: While at the Lighthouse, create a new save file and then reload that save. Some players have found that this can prompt the game to trigger the missing cutscenes or events. I see you did mention this one though.
2. Steam Community
3. Update the Game: Ensure your game is updated to the latest version. Developers often release patches that address known bugs and glitches. For instance, a recent patch fixed various issues, and keeping your game updated might resolve the problem.
4. Workaround

Note: These are potential workarounds and may not guarantee a fix. To mitigate the impact of such issues in the future, it's advisable to keep multiple save files at different progression points.