I tested this with the demo included in the PC package. The Notes version is 5. Can you help me?
There is a difference between a registered LSX, like the ones that come with Domino, and non-registered ones. For the first one, you call an LSX preceded with a start UseLSX "*LSXODBC." For the latter one, you will need to use the full path such has "c:notespcslsx.dll". I do not know if your LSX is registered by the product. I suggest you try the first option first and if that does not work, use the latter one.
Alternatively, you can register the DLL yourself. Look for entries like "HKEY_LOCAL_MACHINE, SOFTWARE, Lotus, Components, LotusScriptExtensions, 2.0, LSXODBC, whose value is "c:notesnlsxodbc.dll," to get an idea on how to do so yourself.