Ok, so I encountered a weird save problem.
I have played around 10 ingame days, and used most of the save slots.
Today I wanted to continue, but it seems that what I saved yesterday is not visible today by the game.
Here are two screenshots (the first one showing example of save nr13 - totally empty in game but visible in its WWW folder, the second one shows a save nr1 that I made yesterday, but it's clearly different what is visible when You compare times):
View attachment 2780588
View attachment 2780589
So, does this RPGM game use another save location and kind of synchronises them?
I am totally confused after playing many of RPGM games, this never occured to me.
Also I must say that I did use some help of save editor, but yesterday I could open my saves even after reopening the game.
Edit:
This is reaaaaaally weird.
I have replaced save nr1 with latest that I saved (renamed save16 as save1), and it did load it successfully.
However this was possible only due to the fact that the game somehow saw some save nr1.