I don't suppose you could be more descriptive of the error?
Also, my first thought when something doesn't work when installed in Program Files, is perhaps it doesn't like paths with spaces in them. I'd be a little surprised if that was the case here, but it may be worth trying it in different folders with and without spaces in the name.
It might also have something to do with where it is installed relative to Outpost 2. I believe it tries to find the Outpost 2 folder to load the resources. If it can't find the folder, that may cause it to fail to load. There is usually an error message about that though.