Part of screen left blank after accessing menu in Zcode game

What steps will reproduce the problem?

1. Load the game Cottage ( http://ifarchive.heanet.ie/if-
archive/games/zcode/Cottage.zblorb )
2. Press Enter when asked to enter date and time.
3. Answer N when asked if you've ventured inside before
4. Type ABOUT to enter the ABOUT menu
5. Press Q to go back to the game
6. Now type a few commands, and note that the upper part of the screen is 
no longer used.

What is the expected output? What do you see instead?

After exiting the menu, the whole screen should once again be used for 
displaying game text. Instead, the upper part of the screen is blank for 
the rest of the session.

What version of the product are you using? On what operating system?

2009-08-25 version, preview 2. Windows XP Home.

Please provide any additional information below.

Original issue reported on code.google.com by fredrik....@gmail.com on 4 Aug 2009 at 9:07

azbycxdw909 / garglk

Part of screen left blank after accessing menu in Zcode game #81