As is always the case, I figured this one out shortly after posting the question. For anyone who runs into something like this in the future I just added a command to my installation script before the invocation of secedit.exe that copied my config file from P:\ to C:\ and then deleted it when complete. Not surprisingly secedit, since it's a security tool, doesn't like loading config files from a network share, even if they're drive mapped.
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Michael Martin
Framehawk Inc.