Right, let me see if I got this straight.
1) You want to use the laptop p3d model instead of whatever Vektorboson used? And display the cutscene script in there?
Well, as soon as I make it work, I'll let you know, this is something that's buggered me as well.
Sorry mate, there could be work-arounds though. Like taking a screenshot of the laptop, cutting a hole in the center, and use the ST_PICTURE style to place it on the screen, and then run the cutscene script as normal.
2) This should be easy enough, have a script that keeps track of the password, let's say in the variable called coolPassword then use ctrlText like Gameer said, and compare that to coolPassword, like so
getPassword = ctrlText idcOfEditField
?(getPassword == coolPassword) : do Cool Stuff
?(getPassword != coolPassword) : ctrlSetText sameIdcNumber "Wrong password"
or somesuch, I'm sure you'll work something out.
3) Almost. Just make a p3d, put it in a pbo, and put it in the addon folder. I think that's how Kegetys did it. I talked to him and he said you didn't need any config.cpp. Just the right selection names for the dialog item.
I suggest checking out the notepad.p3d item from the demo, as it can be used in dialogs. Copy the selections from there.