Maybe I should create a brand-new version 3.4.3 test template instead of
trying to generate a version 3.3.4 template copy. Perhaps, the UI has been
altered with version 3.4.x and is not backward compatible for a version
3.3.x template anymore.
My copy of LO_3_4_chapter_template.ott does not show anything in the
Template field in File > Properties > General.
If I use File > Templates > Edit to open that template for editing and
then use File > Templates > Save to create a copy under another name,
the resulting template (test.ott) does not show anything in the
Template field in File > Properties > General.
However, if I open a new .ODT document from that template and then use
File > Templates > Save to save the .odt as a new template
(test2.ott), the new template does show LO_3_4_chapter_template in
that field.
In addition, generating a template copy by double-clicking it and not
getting the Template field entered could be an unimplemented "feature" in
itself--a bug. Why should one manner work, but not the other?
It's been that way for years in OOo. I believe it's considered a
feature: the idea is that for some documents one might want the
template associated with the file (so when the template is updated,
the file pops up the "do you want to update styles" message); but for
other documents, one might want them based on the template but not
associated with it.
As for undocumented: I had written this up in an earlier version of
the Writer Guide, and I thought the info was still there. Ah, well, my
memory isn't what it used to be. Or perhaps I removed it because the
info was incomplete; there seem to be a lot of non-obvious
interactions. Because of that complexity, this is one of the topics on
my list for extensive research for my proposed book on styles and
templates.
--Jean