Hi Dev! I'm coming from the other comment, thank you again ;\\\\;
I didn't know about the issue of the archive but I have an idea of what causes it, thank you for reporting it!
As for the windows closing and all progress being lost I though I got rid of that bug (screaming internally: OH NO) may I ask in which part of the game you closed the window? So I can check the script... I'm sorry this happened during your gameplay!
Thank you again for playing Deep Inside >\\\<
SPOILER WARNING (vaguely mentioned, but still)
The game froze right before the big reveal at the end of the game. The screen got black as it normally would when entering a new room, but the cutscene didn't load (I think the music didn't either?). If I recall correctly, I could still hear the "next dialogue" SFX, but I couldn't see anything.
However, losing all my progress had also happened before, earlier in the game. I didn't know this would happen and I had to replay everything a a a (luckily I was just starting it, hehe) I think it may be because I had to extract the file with winRAR every time I wanted to reload it, or else I wouldn't be able to open it (?)
But don't worry, it's no fault of yours! Still had a lot of fun playing and getting to know the characters during the tea party events was such a cool feature :]