If Hopper's idea doesn't work….
I'm not very good at this sort of thing, but maybe some of this will give you an idea or two.
I presume the Tab key opens the doors and works the terminals, it only crashes when you try to save a game. This sounds weird, but does your tab key actually do the tab function? Some computer makers, to increase the pleasure of your computer experience, actually recode some keys to do things that practically no one in the known universe wants to do. I had to redo all the function keys on mine to be function keys.
How do you play? Do you start AlephOne (green icon) then from a list choose which scenario you want to play, or do you go, for example, into the Marathon 2 folder and click the brown icon which loads the game directly without you having to choose from a list? On my system, the .exe's in the separate folders are the older version and the AlephOne is the newer one. Last night, I did both ways for all three games and they all saved properly in their respective manners. I have only downloaded the 20150620 version of AlephOne. My M, M2, MI, .exe's are from 2012 & 2014. Perhaps you can find an older version of the .exe to try. The "download" link on the S'pht on the home page may still have them available.
The save file is two folders: one called Quick Saves, the other called Image Cache. Both are in the Aleph One folder which should be at the Widows 10 equivalent of:
XP = C:\Documents and Settings\*username*\My Documents\AlephOne
Windows 7 = C:\Users\*username*\Documents\AlephOne
In the Quick Saves folder there is a subfolder for each game: Marathon, Marathon2, Infinity, Eternal, etc.
On the older versions the single save folder is named Saved Games and everything is in there, but names only, no maps.
If any of these folders don't exist, the program usually creates them when needed.
As Zetren says, it might be something with permissions and/or user accounts. I have run into this several times when trying to write or copy files. Perhaps the account that plays the game is not one that can write to the folder.
If it's just your computer, you can give your user all authority to AlephOne and the Quick Saves folder & subfolders and Image Cache folder.
It may just be your particular computer. My XP will immediately exit if I try to use the m command for the map. My W7 will do the m command, but when I exit AlephOne playing Eternal, it gives an error that program has stopped working and I need to end it (though it hasn't always done this), but only for Eternal, not for any of the other games.
Here is something else to try. On the main menu, go to Preferences>Environment>Solo Script then select the Cheats.lua script, then during the game (anywhere you want) use the console command, \ key, then type in yourmom() <Enter> on the command line and see if that works. Albert Einstein once defined insanity as doing the same thing again and expecting different results; but then ol' Al never used Windows.
Another thing to try is to set it to run in a compatibility mode for Windows 7 or 8 for example. It might be one of the programs that W10 can't run. Any other W10 users around?
If you already know and/or have tried all of this and/or none of it applies or works, well, we haven't lost any ground and have gotten some typing and posting exercise.
I just play 'em; I don't know how they work.