What is the correct procedure to install multipart games-keep getting installer files missing!?

download the multi parts of a game
either in your browser
via gog downloader
or galaxy ( if you must )

double click on the installer
and follow the on screen instructions

the installer will do the rest

Usually, you just have to put all the parts into the same folder and start the installer .exe.

See attachments.
Replace the Stasis/Neverwinter Nights examples with whatever game you're trying to install, of course. :)
(Step 3 is the part most relevant to your question, but I just went ahead and posted the whole thing. :) )

I am getting -- Installer files missing-please make sure you have downloaded all the parts.You will be asked for their location during installation.Integrity check will be skipped.
I get this message after selecting English as the language.

First things first: Which game are we talking about?

(HunchBluntley (post#4) has given you a step-by-step instruction, btw.)

the night of the rabbit- other games also-files went somewhere??things are frustrating-please help!

Ah, too bad, that's one, I don't own...else I have given you screenshots, to show you what your DL-folder should look like.

But have you tried to follow HunchBluntleys instructions?

To give you an example (here Driver): (see attachment)

You should have a setup file with a golden symbol, and one or several .bin files

If you doubleclick on the setup file with the golden symbol, it should start the installation.

What was your method of downloading? (Browser/GOGDownloader/Galaxy)

I remember - some years ago - when I used the browser, I had to watch out for the .bin - parts to be correctly downloaded.

Sometimes it (the browser) wanted to open the .bin files, instead of downloading/saving them...which lead to errors then.
Maybe this is the same here?

I used GOG downloader-under the rabbit in gog there is nothing-any suggestions?Single file downloads are ok.

Hmm,...like I said - NotR is one of the few games here on GOG, that I don't own, so I cannot show you how it should look like, resp. I cannot try to download the files on my own to see if there is maybe an error in general.

Have you considered to download the files via your browser?

It's not the perfect solution - but it would let you play the game.

And - if the same error occurs after downloading with the browser - you know, there is something wrong witth the files as such...in which case I would contact support (however, it's weekend - you'll likely have to wait til monday, for an answer).

Would turning off Norton security help?

You have Norton!?

I'm shocked you got the computer on to begin with.

Well, taking my own very bad experiences with Norton into account - it might help...but I can't say for sure, really.

Try it - or download via your browser...your choice.

Maybe a stupid question but how do you download using browser-explorer 11 I have.By the way thanks for being patient with me appreciate your help very much!

There are no stupid questions - only stupid answers. ;o)

I don't use IE, but the procedure should be the same anyways:

Go to your account tab
go to the game (NotR, in your case)
click on the game
click on the file(s) --> see attachment

EDIT: in case of multiple part games, you have to click on every part, of course. :o)

EDIT 2: added a screenshot with a multiple files game