Hello Luluiron
A solution via console is usually not helpful, as it can cause errors that are only visible later and then it is unsolvable.
OpenMW could be a problem, but I can't say anything about that.
We can't suport that either, only the creators can do that.
Unfortunately I can't test your saved game because I can't play the English version.
Here is a forum post about installing on Steam, but in German, with pretty detailed instructions on what to do or why it doesn't work otherwise.
You need a Steam_Morrowind_installation and the
Morrowind code patch (But I still use the old version 2.0 for Arktwend, so I don't know the latest version.).
This resets the date of the archives to the original date of Morrowind and so replacermods can also work with Steam.
(I would leave everything as it is in the MCP menu.
The important thing is to reset the date!)
I myself have never tested this option!
I hope I can help you with this,
but it's possible that your save game has been modified by OpenMW and is therefore not compatible?