Got the 'XP look' on one PC, not on another. What's different?

Using a Make My Manifest manifest file, my VB6 app displays with the
nice XP look (rounded buttons etc) on one XP installation, but on a
different, newer XP the 'traditional', non-rounded look is evident.
The app is being run from the same USB stick in both cases and both
PCs are up to date with service pack fixes etc.

What is missing from the one PC? Where do I start looking?

BTW, this is what I call from Sub Main:

Sub InitCommonControlsVB
Dim iccex As tagInitCommonControlsEx

With iccex
.lngSize = LenB(iccex)
.lngICC = ICC_USEREX_CLASSES
End With

InitCommonControlsEx iccex
End Sub



GenProcs.Bas includes:

Type tagInitCommonControlsEx
lngSize As Long
lngICC As Long
End Type

Declare Function InitCommonControlsEx Lib "comctl32.dll" _
(iccex As tagInitCommonControlsEx) As Boolean



The manifest file includes:

<dependency>
<dependentAssembly>
<assemblyIdentity language="*"
name="Microsoft.Windows.Common-Controls" processorArchitecture="X86"
publicKeyToken="6595b64144ccf1df" type="win32" version="6.0.0.0" />
</dependentAssembly>
</dependency>


NB: on the PC where the effect is missing, the comctl32.dll in
\Windows\system32 is ver 5.82.2900.6028, but there are several other
files of the same name dotted about. For instance, there is a
comctl32.dll ver 6.0.2900.6028 in the folder
C:\WINDOWS\WinSxS\x86_Microsoft.Windows.Common-Controls_6595b64144ccf1df_6.0.2600.6028_x-ww_61e65202

How come the one in system32 is older?

Thanks!

MM