Thank you for providing the handviewer tool, with which I am very pleased. I am planning to use it in a course on card play, and unfortunately I have encountered a problem, hopefully caused by my not being familiar enough with the tool. If not, consider this a suggestion for modification. Setting up an end game situation, i.e. with less than 13 cards in each hand, the Play-button fails to let me control the play. The situation is set up with an a-argument, as for instance a=-sd to have south play with diamond as trump. Clicking 'Play' then does not indicate player's position with the usual yellow marking and consistently does not allow a card to be picked. Of course I can arrive at the desired situation by playing from trick 1, but only in the minority of cases is that relevant and tolerable. Usually I want to focus on the interesting situation. A guide to a proper way of using handviewer will be appreciated. If the problem requires a serious programmatic effort to resolve, it might help with an additional parameter to spool over a given number of tricks or card plays or start at an indicated trick number. It will require an additional effort by an author, but at least provides a usable fix. It will be more convenient for viewers.