takjas: Hi all. You should be able to play D4xB8 or D4xF8. For me these are the correct moves. However, if you can't play them, please try D4xB3 or D4xB2 or D4xB1 through D4xD6xD8xB8xB3 or B2 or B1.
takjas: Try something: move d4-d6-d8, then move your cursor over each square on the board to see if the arrow becomes a hand. It could be a square which doesn't make sense. If it becomes a hand just go there.
Anyway it's probably just a bug in the game, which is too bad because Fencer no longer corrects them. You'd better resign, otherwise this game will just eat away your vacation days.