Windows 7 64bit.
I have downloaded the game successfully. I have sound. Game opens in dosbox okay. I have been able to navigate through the initial screen scene using the forward/backward and left/right navigation cursors. No other cursors are appearing. When I right-click on the mouse, no inventory appears. Re-loaded. No good. Am I missing something here?

Did you actually pick up any objects yet? From what I remember, you don't start with anything and there isn't much to pick up early in the game. As far as I know there is no inventory screen, so until you find something to carry around, right-clicking to cycle through the inventory does nothing.