[HD2 Windows Mobile 6.5 Themes and Apps] Lukasss:
Try the file in the attachment, copy it to /Windows/Lockscreen on your device.

I modded mine to display the clock only, and I deleted the clock now, but haven't tested it. So please take a backup of the existing LS_LockScene_480x800.cpr in /Windows/Lockscreen, so that you can go back if something doesn't work.

Softreset after you copied the file, and use the default windows lockscreen, not C00kie's lockscreen...

Let me know if it works. You also can edit LS_LockScene_480x800.cpr in wordpad or another text editor. The layer ID's explain themselves. I just deleted the following:

<Layer ID="TimeAppointment" Top="540">
<Layer ID="DateTime" Top="14" OnInitComplete="Binding:LockScreen,LS_ClockDataItem">
<Text ID="TimeText" Top="-2" Width="288" Height="68" FontFamily="Helvetica Neue OTS" FontSize="28" FontStyle="Regular" Wrap="False" VerticalAlignment="Middle" HorizontalAlignment="Right">
<TextStage TextOffsetType="TextOffsetDropBottomRight" Color="#00000000" TextOffset="1" BlurFactor="3" />
<TextStage TextOffsetType="TextOffsetNone" Color="#FFFFFFFF" />
</Text>
<Text ID="AMPMText" Left="300" Width="180" Height="32" FontFamily="Helvetica Neue OTS" FontSize="9" FontStyle="Regular" Wrap="False" VerticalAlignment="Middle" HorizontalAlignment="Left">
<TextStage TextOffsetType="TextOffsetDropBottomRight" Color="#00000000" TextOffset="1" BlurFactor="3" />
<TextStage TextOffsetType="TextOffsetNone" Color="#FFFFFFFF" />
</Text>
<Text ID="DateText" Left="300" Top="33" Width="180" Height="38" FontFamily="Helvetica Neue OTS" FontSize="11" FontStyle="Regular" Wrap="False" VerticalAlignment="Middle" HorizontalAlignment="Left">
<TextStage TextOffsetType="TextOffsetDropBottomRight" Color="#00000000" TextOffset="1" BlurFactor="3" />
<TextStage TextOffsetType="TextOffsetNone" Color="#FFFFFFFF" />
</Text>
</Layer>
<Layer ID="Appointment" Left="5" Top="100" OnInitComplete="Binding:LockScreen,LS_Appointment">
<Image Width="80" Height="82" Visible="True" ScalingAlgorithm="TriLinear" Source="\windows\htc_icn_cal_up.png" />
<Text ID="Subject" Left="86" Width="360" Height="35" FontFamily="Helvetica Neue OTS" FontSize="10" FontStyle="Bold" Wrap="False" Trimming="EllipsisCharacter" VerticalAlignment="Middle" HorizontalAlignment="Left">
<TextStage TextOffsetType="TextOffsetDropBottomRight" Color="#00000000" TextOffset="1" BlurFactor="3" />
<TextStage TextOffsetType="TextOffsetNone" Color="#FFFFFFFF" />
</Text>
<Text ID="Time" Left="86" Top="36" Width="360" Height="30" FontFamily="Helvetica Neue OTS" FontSize="8" FontStyle="Regular" Wrap="False" VerticalAlignment="Middle" HorizontalAlignment="Left">
<TextStage TextOffsetType="TextOffsetDropBottomRight" Color="#00000000" TextOffset="1" BlurFactor="3" />
<TextStage TextOffsetType="TextOffsetNone" Color="#FF999999" />
</Text>
<Text ID="Location" Left="86" Top="67" Width="360" Height="30" FontFamily="Helvetica Neue OTS" FontSize="8" FontStyle="Regular" Wrap="False" Trimming="EllipsisCharacter" VerticalAlignment="Middle" HorizontalAlignment="Left">
<TextStage TextOffsetType="TextOffsetDropBottomRight" Color="#00000000" TextOffset="1" BlurFactor="3" />
<TextStage TextOffsetType="TextOffsetNone" Color="#FF999999" />
</Text>
</Layer>
</Layer>