The newcommer appears only after you show fake badge to the centurion, judging by the file NPC_MDN_Centurion_01.xml:
- <dlgPart>
<portrait />
<speaker_name />
<npc_text>“It’s a fake,” says the centurion, barely glancing at the badge. “Last month, we crucified three men for selling these badges, but I guess people like you make it too tempting for them.”</npc_text>
- <onLoadScripts>
<string>aod.npc_centurion_talkedBadge = true;</string>
<string>dlgRemoveItem(2178, 1);</string>
<string>dlgAddItem(2176, 1);</string>
<string>createByCharMarker("CM_MDN_NewComer");</string>
</onLoadScripts>
- <answers>
- <dlgAnsw>
<text>“Do I even need a badge?”</text>
<def_link>7</def_link>
<checkOnAppear />
<checksOnClick />
<linksOnClick />
<scriptsOnClick />
</dlgAnsw>
</answers>
<UID>1</UID>
</dlgPart>

It was there since ver 0.8.8.0116 (Public Beta R4.3) - Dec, 2013!

Oh wait I wasn't talking about the newcomer specifically - though I thought she rocked up straight after the guy sold you his ticket. I completely forgot about the step in between, that is, as you reminded me above, requires showing the ticket to the centurion and THEN she shows up.

The part I'm talking about is the fact that the guy selling you the ticket only shows up the first time you go to the palace district (I believe dialogue with him is automatic as soon as you enter the district) - but if you visit Domitius (not what I thought his name was above) first, you're teleported to Gaelius, and if you visit the palace district after that, he never shows up in that game (because I think once you've been the the palace district, the dialogue (MDN_GatePalace_01.xml) doesn't trigger any more - possibly because some var is set somewhere when you enter the district, and you enter when exiting Gaelius's palace?).

Like I said this might have been changed somewhere ages ago, but I never noticed because I always make sure to visit the palace district before seeing Domitius.

That file has been calling from Maadoran.mis file, and only once - judging by the flag aod.mdn_explore_gatePalace:
new VirtualObjectCollision(VCO_GatePalaceFromTrade) {
script = "if(aod.mdn_explore_gatePalace == false)\n{\nBlackSplash.command = \"\";\nBlackOut.command = \"sd(MDN_GatePalace_01); schedule(50, 0, centerCamera, 0, 40, 20); startBlackSplash();\";\nstartBlackOut();\naod.mdn_explore_gatePalace = true;\nrevealMapLocation(\"MaadoranNobles\");\nrevealMapLocation(\"MaadoranPalace\");\n}\n\nelse\n{\nBl ack Splash.command = \"\";\nBlackOut.command = \"dlgTeleportToMarker(TM_Gate_PD); schedule(50, 0, centerCamera, 135, 40, 20); startBlackSplash();\";\nstartBlackOut();\n}";
active = "1";
combatActive = "1";
cursor = "Door";
cursorText = "Go to Palace District";
interactDistance = "0";
iconHeightOffset = "-2";
polyhedron = "-0.5000000 0.5000000 0.0000000 1.0000000 0.0000000 0.0000000 0.0000000 -1.0000000 0.0000000 0.0000000 0.0000000 1.0000000";
gameFloor = "-1";
position = "99.9962 -13 9.53674e-07";
rotation = "0 0 1 90";
scale = "1 4.48821 5.80088";
isRenderShadowEnabled = "true";
canSave = "1";
canSaveDynamicFields = "1";
persistentId = "9a02a976-a062-11e2-b818-894ff0869547";
};
It hasn't any connection with Gaelius' inside-palace events.
It's similar to version 0.9.0.0021 (May, 2015).

Right, I think I know what must have happened now: when leaving Gaelius', you end up outside the palace; however, since I wasn't transitioning TO the palace district from another district (since I just came from the palace), the above didn't trigger - therefore I didn't find the ticket-seller.

So it looks like all I had to do was re-enter the palace district from the trade district, and this would have triggered as normal... Unless of course mdn_explore_gatePalace was set to true by some other method/function - which is possible, but it would make more sense that the only thing setting that variable is the above code (to ensure it's run only once)...

And I guess I just assumed that he wouldn't appear when I re-entered the district... My bad. Well you know what they say about "assuming" (echoes of many past teachers ring in my ears. Also Harold from Fallout 2).

My bad - next time I'll just play without worrying about where I go first. Can't believe I was being careful for all those playthroughs...

Yeah I did the same thing before I wrote that post - by which I mean I just did a text search for aod.mdn_explore_gatePalace through all directories and archived files in AoD's main dir, and it only came back with that file. Thanks for checking though - I probably should have checked ages ago instead of just assuming...

You're welcome :)