Um, have you tried Saving the game (... > Overwrite) right after you see a problem, then loading e.g. Chess, then loading this saved game?
It is crucial to load a different mod between loading the save, otherwise TTS would not refresh images. Turning time back does not help, it won't force proper loading of the images.

Don't be afraid to save your game even when it seems to be buggy. Most of the problems will fix itself.
Making separate cards would not be that big of a problem, but writing their names would take a loooong time. There would need to be some scripting support to allow you to change the cards easily, possibly with cards visibly flying somewhere and back. If I understand TTS correctly, card image cannot be changed in decks (CardID is neither accessible for reading, nor allowed to change).

Yeah, can't finish any game. Each time either (1) a card moves to the top of the deck and remains there after shuffling, etc, and when I restart (3) below occurs or (2) I hit back button but have to make different move than planned -- sometimes works, but eventually I hit either (1) or (3) I have to restart after a card turns black/white and can't be manipulated but the resulting saved game is many turns earlier than the failure and I lose a ton of progress. Super frustrating, because this mod is so excellent. Obviously you put some effort into overcoming the problems of TTS, but... until they address the stability issues.

I think the only workaround would be to have a searchable set of cards in which each flipped side is an individual card.

Thanks for those responses! Most kind of you.

2) No idea about the Field Hand / Servant, but seems to be an issue related to states, i.e. 3
3) TTS has problems with states and custom decks. Sometimes it fails to load it (or loads it weirdly like parts of other cards). I could not find any way to force reload without breaking everything about the affected card. I tried to add a hot-fix that refreshes the image by forcing a state change to 1 and back again, when you hover over a "black" card. It does not work on state 1, though (when I force change to any state, it turns into a "white" card and we're screwed). However, there is a little longer, but 100% reliable solution. Save the game, load another game e.g. Go, reload this save. All images should be fixed.
Hope these help!

@turton.michael: OK, so there are a few different issues you mention. Let's tackle them one by one, each of them comes from the limitations of TTS:
1) Decals - they are part of the object they are stamped on. Object means card OR deck. And TTS cannot display decals of the other object type. Take a deck, place decal on the top - it will be on the deck, not on the card. Otherwise, placing a decal on a card and then moving it to the top of the deck will "hide" the decals, but the card still has them and you can see them when searching the deck. So to me it seems you stamped a deck, not the card.

The strange problem of the Field Hand did not reappear in subsequent games. Decals, though.

Decals didn't stick to the card I put them on. And they displayed on all cards in the draw deck above that card. Each time I revealed a new card from the draw deck, it showed the decals on it, but when I moved cards to the play area, the decals disappeared -- including on the card I put them on. *sigh* it's really too bad. A great game and your version is wonderful, but major issues for me. Every Round the first card I play is the female field worker, because it won't shuffle into the deck (see below). It just displays 2/2 Servant when I mouse over it. Once I played her, mousing over it shows the correct number of cards in the deck.

Got a problem. I have the Field Worker. Each time I am finished with a round, she ends up on top of the deck even after shuffling. If I take the deck apart and put her in the middle, after I shuffle she moves to the top of the deck. If I shuffle more than once, she changes state and becomes the Field Hand. Very frustrating.

Darn, I have to restart yet again after realizing I did the 'purge' instruction incorrect. (I drew 12, and purged 1 card, and thought I was done. Nope, it's meant to be a purge for *each* 12 cards.)

I can't imagine the frustration for people who pick this game up as a physical version and then realize 1-2 expansions in that they messed up some important rule early on...

wait, you don't have any issue with cards going white or black in the game? :o

@separateunion: Stickers can be added through the Decals (menu on the left, the next to last option on the bottom, I believe). Select a decal with the right name, stamp it on the card, change back to the "hand" tool in the same menu.

How do you add stickers to cards?