Is there a limit to how many screenshots can you save in the folder?

I've got the GOG version and I've been saving them to the default folder. Everything worked just fine until Sunday, but yesterday after playing I noticed that none of the taken screenshots were saved. Just tried to take a new one today - no can do.

Is anyone experiencing the same?

EDIT: solved - the formatting of the filename threw them in the middle of the folder, had to rename to keep them in order.