[plt-scheme] Startup Problem

I have PLT-Scheme (plt-4.1.5-bin-i386-win32) on Windows (Vista).

When I start it it, it opens a "Standard Output" window, with this message:

    draw-bitmap in dc<%>: expected argument of type <bitmap% object>; given #f

     === context ===
    E:\Program Files\PLT\collects\drscheme\private\drscheme-normal.ss:208:15

DrScheme was working before this came up, if that helps.

This happened even after I reinstalled it, so maybe there is something
left behind after an uninstall that I must remove?

I even upgraded to plt-4.2-bin-i386-win32 and the problem remained, so
what stays between installations?  Registry entries?

Any help would be appreciated.

Regards,
Roshan Mathews