Generating a print doc deletes other docs in the same directory

Generating a new doc into a directory that contains a different doc generated off the same Word template causes the older doc to be deleted.

MY RH8 project is set up with a number of Print Documentation SSLs, one for each chapter of a book, all to use styles from the same Word template. Each SSL has the same Location selected, so all the chapters are by default created in a common directory, where each can be tweaked as needed and later all merged into a single PDF for distribution.

But as each doc is generated, the previously-generated doc in that directory disappears. The newer and older files have different file names, were generated by different RH Printed Documentation SSLs, but the SSLs refer to the same Word template. If a previously-generated doc is still open in Word when I generate the next, then I get the "[template name] is locked for editing" prompt, I select "Open a Read Only copy", it runs on to completion, and then both docs are present in the directory as expected.

The selected output can be doc, docx, or pdf, and always the earlier file is deleted. The selected Location in which the files are created can be inside the project or outside the project. It makes no difference whether the template's properties are set to Read-only.

An obvious workaround is to copy each file out to a different directory as soon as the file is generated. But RH deleting differently-named files is so obviously a malicious thing to do, I can't be working it right. Any ideas?