It might be because the version of VeSys you are installing doesn't support that version of AutoCAD.
How are you doing and where are you working now?
Mentor Graphics no longer provide support for VeSys Classic running on AutoCAD LT, if the installer does not find a suitable version of full-AutoCAD (2004-2009) then only VeSys Compoents is installed.
I hope this information helps,
It was working in the past, any ideas if an older version of VeSys used to run on Autocad 2002 LT?
I am at Terex now!
I'm not 100% sure which versions worked with AutoCAD 2002, you could try 2008.1 or even 2007.2.