I would say this is by design, or simply a consequence of how Execscript works. The program/command you execute via Ececscript does not see the environment it's called from, it only sees Windows.
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>Solved somewhat (still parts to check). Cause was ExecScript(). If form is called via execscript then it fails (a bug or a by design???) and doesn't see files included in project.
>Cetin