Mark,
In a vfp com dll, you need to specify your paths beginning with where the DLL is run from. You should use this for your datapath statement:
JUSTPATH(Application.ServerName)+"\"+YourDataPath

Our setup for ActiveVFP and ASPvote (download section)do the same thing (I think) you're trying to do with InstallShield..

>Background facts:
>I am using a setup that I created in InstallShield Professional v6.2 to install a VFP 6 application. I need to run some VFP code during the setup process so I created a VFP COM DLL with a class in it that I am instantiating during the InstallShield setup. Within the COM DLL I have a method that is calling a function that lives in a seperate VFP EXE in order to open a table that is contained within that EXE. (Once the table is open the method in the COM DLL will use it as a lookup table.)
>
>Problem:
>When the line of code runs that actually issues the "USE" command it is unable to find the table even though the table is contained within the very EXE that is trying to open it. If I call this same function from within the main VFP application the "USE" statement works fine, its only when called from my VFP COM DLL, which is running via InstallShield, that the problem occurs.
>I know the "USE" statement is executing because the InstallShield error message explicitly mentions the table that it is unable to find by name so everything is running fine up to that point.
>
>I don't understand why the table can be opened this way when the function is called from within my main VFP application and not when called from my COM DLL running within InstallShield.
>
>Additional facts:
>* I don't want to include the table in my COM DLL for reasons that I don't want to take the time to explain here.
>* Everything else works perfectly. If I don't try to run code in another EXE that opens a self-contained table all is well.
>
>Any ideas or suggestions would be most welcome.