The same procedure should work on Windows 7 too, but they haven't yet updated the article.
C:\>reg query "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\SubSystems" /v windows
windows REG_EXPAND_SZ %SystemRoot%\system32\csrss.exe ObjectDirectory=\Windows SharedSection=1024,20480,768 Windows=On Sub
SystemType=Windows ServerDll=basesrv,1 ServerDll=winsrv:UserServerDllInitialization,3 ServerDll=winsrv:ConServerDllInitialization,2
ServerDll=sxssrv,4 ProfileControl=Off MaxRequestThreads=16
Increase the bolded number. It'll be substantially smaller on 32-bit windows (the example is from the 64-bit box on which I'm typing this).
Just FYI, the size of those parameters has very little to do with the amount of RAM. Going back a looong way, parts of this code are from pre-NT versions of Windows. So-called GDI objects don't live in the "Object Manager" namespace, but instead in a separate area used for storing "GDI objects" (window elements, icons, buttons, cursors...).
When the visual complexity of the stuff you've got on screen reaches a level where the storage area is no longer sufficient to store all those windows, buttons, checkboxes..., you've run out of a resource called "desktop heap", and that's what the error message is really trying to tell you.
What sort of program is it, just out of idle curiosity?