What is a "PI marker" or "programming instruction marker"

[David Artman]

Hi, all--FM8p277 on Win7. This is a long post, but I want to be thorough
and to show that I've done my due diligence to solve this by myself.
 
Trying to use DITA2Go (D2G) to produce Compiled HTML Help (CHM) with
context-sensitivity.
 
According to D2G Help, I must "Place a 'TopicAlias' PI marker in the
text of [my] document where [I] want to display context-sensitive help."
[D2G Help 18.11.1]

OK, new marker type named "TopicAlias": no problem.
Contents of a marker of that type "IDH_about": no problem.
(I inspect the XML in an editor, and the '<?FM MARKER [TopicAlias]
IDH_about?>' is within the TITLE tag. I'd *kind of* prefer it to be
before the tag... but I can not figure out how I would place there using
the FM interface; and there's *no way* I'm going to place/move hundreds
of these markers manually!)

Project is setup as much as I possibly could in D2G Project Manager--I
mean, I've checked *everywhere*: every INI file in the stack and every
tab in the UI. I've added every line of code to the project INI file
that the D2G Help says is needed for alias files (i.e.,
'MakeAliasFile=Yes' and 'AliasPrefix=IDH_' and 'UseAliasAName=Yes').

Press "Start" button... Lo! A CHM file, which opens showing the page to
which I want it to default. And I go to check in the output folder,
because "When you use PI markers for CSH destinations, by default
DITA2Go generates an alias file for you, named after your document, with
extension '.hha'...". [D2G Help 18.11.4].

Um, nope. No HHA file in the project folder (nor even on my entire hard
drive--yes, I searched). So I'm having some doubts that the CHM would
work, if delivered to the development team, because "If you use PI
markers for CSH destinations, you need both a map file and an alias
file". [D2G Help 18.11.2]

Additional note: there is no '#include "My_Project.hha"' line under the
'[ALIAS]' section of the project's HHP file. I could add one easily; but
lacking the file to which it refers, it seems pointless at the moment.

So I wonder... what is a PI marker, if not what I'm placing? I've tried
showing every possible element, including invalid ones for the location
at which I want the marker (before the TITLE element), but I see no "PI"
element that I could use.

Any help? I'd check on the DITA2Go forums, but they seem a bit on the
dead side. So I'm turning to my fellow Framers because, if nothing else,
I need to be able to do it consistently in FM, not by hacking away with
a text editor.

Help me with HELP!
David Artman