I experienced this same problem. Apparently this is due to the change Sun -> Oracle of VirtualBox.

There's a workaround I found out, that works:

Export The Registry key HKLM\SOFTWARE\Oracle\VirtualBox (with content) to a file.
Open the file with notepad. Replace Oracle with Sun in the registry key ONLY (NOT also in the key entry that point to the path were virtual box was installed!).
Save. Import file with change into registry.
Voila. Now the vmlite xp mode plugin installs!

Reg. file content that did it for me:
REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Sun\VirtualBox]
"Version"="%VER%"
"VersionExt"="4.1.12"
"InstallDir"="C:\\Program Files\\Oracle\\VirtualBox\\"


Greetings,
Leo Smulders

Unfortunately, in my previous reply I was too happy too quick:

After the install, upon starting VMLite (Run As an Administrator) I get this:

The procedure entry point CPUMGetGuestMsr could not be located in the dynamic link library VBoxVMM.dll.

(My VirtualBox is: V 4.1.12r77245)

Leo Smulders

Hey
I think I have a similar problem.
I installed Sun Virtual Box Version 3.0.14 and the VM Lite Workstation Plugin (I would like to use my old scanner in Windows 7 64 Bit) but if I start the VM Lite workstation I get the error massage: "The procedure entry point DBGFR3AsSymbolByAddr could not be located in the dynamic link library VBoxVMM.dll."
Can anyone help? I invested a lot of time to get to this point!
That would be great.
cm

Same problem. Wasted my time.