I am not sure of what you mean by "play the game forwards".
I am using a laptop with windows 7. Here is how it all works for me.
From the regular game board I can select game analysis, which takes me to a page showing the game at it's current position. I can then move all of the pieces around as I wish, including those of my opponent. I can also add pieces to the board wherever I want to place them. Closing that page will return me to the regular main board.
From the main board I can also select game history, and from there I can replay the game back and forth from the opening position to the current position, but I can not rearrange any pieces and cannot go forward past the current actual position.
From the "game history" page I cannot go to the analysis board. I can only return to the main board.
I am not having any problem in doing any of the above actions. As far as I know, the only way you can play the game forward from your current position is with the analysis board. However, the analysis board allows you do whatever you want with all of the pieces, even if it isn't a legal move.
I don't know if any of this has been or help for you or not.