What DJ said is right. That was an old template.
Unless you use a recently updated template (especially made compatible with v2.4), consider every old template listed here, as NOT compatible with the latest v2.4. But also keep in mind that v2.4 is still beta/experimental, so IMHO, it's recommended to stay with the stable v2.3m (until v2.4 goes stable, but then you must adapt that old template or use a modern template designed for v2.4). There is no other option.
I use 2.3m and want to make VLC running. I tried 2.4 RC06 but it hints a Template Error. Actually I try to prevent editing templates
Sadly, if you want to use that template, you must keep using v2.3m. The is no other solution, since v2.4 is 'by default' incompatible with older templates (unless you adapt the old template to the changes introduced on v2.4).
Chrome force open link not download (or adding Header Content-Disposition: inline should also do, but don't (possible a bug))
That's right, if I'm not mistaken, something possibly related was already reported (3 years ago) by Mars
here:
Unfortunately since several versions, Rejetto has deleted an extension of the ADD HEADER macro to add an option to an existing header.
...but Mars didn't say in which version that function was removed.
Cheers,
Leo.-