Hey Jayhawk. Global characters require a few extra steps for dialogue to work if you're making a standalone mod. They worked in the tutorial videos because those videos are based on modding the main game.
I just posted a walkthrough on this, I'll put it here as well. Let me know if you have any other questions.
First - you need a global character, and you need to change that global character's name on the "Characters" tab (Red stick figure at the top of the screen). Change it to something you can reference easily. For this example we'll use "QuestGuy".
Once the Character is global, you'll notice his dialogue no longer activates in game. This is fixable.
Open the story editor, and if you haven't already, you need to make a goal called "_Start". In "_Start" put the following:
Init:
CHARACTER_Player1.isPlayer();
CHARACTER_Player2.isPlayer();
KB:
IF
GameEventSet("GAMEEVENT_GameStarted")
THEN
InitStory();
GoalCompleted;
//This assumes you've changed your character names to Player1 and Player2 on the character tab.
Exit: Can remain blank
For a quest NPC, you'll want to open the story editor and create a new item (actually it's called a "goal"). Create your new Goal and name it whatever (I name mine after the Quest NPCs for easy reference. I named mine "QuestGuy". Drag it into the _Start goal so it's a child goal to _Start. _Start should be expandable now to see your child goal.
In your new Child goal "QuestGuy" or whatever you named it, you can leave INIT blank for the time being.
In KB Put the following:
IF
DialogStartRequested(CHARACTER_QuestGuy, _Player)
THEN
DialogStartTwoSpeakerDialog("QuestGuyDialogue",CHARACTER_QuestGuy,_Player);
"QuestGuyDialogue" is the name of whatever you saved your dialogue as in the keyword editor.
All of that will get Dialogue working for you.
The Larian tutorials for dialogue in the Scripting Quests videos will all work now, apply what you need from those videos to your own dialogue.
Edit: you can do all your quest scripting for this character in this same "goal". I just put it below the dialogue call in the KB section.