This would be nice if it actually worked. For starters inside the data.dat there are no other dat files inside there. just folder
data
agentaliases.txt
companya.txt
companyb.txt
fornames.txt
gatewaydefs.txt
newgatewaydefs.txt
providers.txt
spam.txt
spam_t.txt
surnames.txt
wordlist.txt

fonts

graphics
analyser
awards
dialler
gateway
hud
irc
lan
loading
logos
mainmenu
records
software
start
upgrades
vdpin

music

sounds

Thats the folder and file structure. theres other files but none of them are .dat Also there is no graphics\graphics\gateway theres not even a graphics\graphics.

After several trial and error, it work for me. Accidentally, i deleted data.dat in the uplink folder, yet the game doesn't experience any trouble. I think those in uplink folder won't have anything to do with onlink after initial installation.

The file must be placed on the folder onlink/data/newgatewaysdef.txt (edit it by adding the custom gateways information, don't forget the Ram), then paste the graphic on the folder onlink/graphics/gateway. And i mess up my folder with excess copy paste, so if those doesn't work, that's mean i missed something and successfully add new gateway by luck. I'll try it again on my second gateway tomorrow.

I know how to do it in uplink the process explained was much the same but alot of the files the person said do not exist like graphics.dat

Alright, i've confirmed it and installed my 3rd custom gateway without problem. You don't need graphic.dat, once you extract data.dat (or in my computer, data without extension), you'll have folders: data, fonts, graphics, music, and sounds; make sure those folders are in directory onlink (not uplink).

Next, you'll need to place the txt file (gateway data, ie gatewayName.txt) in onlink/data/gateways (if gateways folder doesn't exist, create a new one). Make sure to add MaxRam number, should be between first and second number you encounter in gateway data (first would be maxCPU, second would be maxMem).

Next, copy the two .tif file (for graphics) and place it in onlink/graphics/gateway along with the other gateways graphics. There you have it, run onlink and you should see the custom gateway in uplink internal service under gateway upgrade. At least it work for me, and without modifying newgatewaydef.txt file.

Isn't there a MaxUpg war right after MaxRam?

Nope, sequentially from left to right, Name, Cost, MaxCPU, MaxRam, MaxMem, MaxUpg, MaxSec, Bandwi, Width, Height, Description. Then again, i forgot about the cost ==a that would be between the second and the third number, not the first and the second.

Okay, this is corrct. Remember that MaxUpg are hardware upgrades that use 32x32 slots and will appear starting 0.2.0.

what kind of upgrade?

There's going to be two new things in 0.2.0. Cooling units and "hardware upgrades"

Cooling units are used the same at CPUs. If you have a cooling unit on a CPU, the image will change for it. Nothing fancy. HW Upgrades, aka SATA II, are for special equipment, like a panic switch, special receivers for modems and managing requirements for special coolers (i.e. a managed pump for liquid cooled systems).

You will need at most 3. Typically.

I noticed that the sizes maximum of the image of the gatway are 700x500 in the big illustration and 200x140 in the small illustration, however all big illustrations are in smaller size than 700x500, seemingly they are not knowing the limits.
he/she/you also can he/she loses temper ros sizes of the cpu illustrations, ram and memory, he/she grows up like this more detailed illustrations.
The program gatewaymarker not supposed size 700x500 he/she needs to adjust with reverse engineering, unless somebody has the program source, but it is possible to create illustrations in these sizes in the photoshop or similar.
The illustration below is initially the prototype that I am creating, it was for uplink, I intend to add RAM's, I accept suggestions

dude thats not a gateway thats a whole lan.

That is a praise?
the illustration below is the final model, I believe... nobody gave any suggestion...
8 CPU
memory 32x8 = 256
RAM = 3 CARD

I am having difficulties of inserting some new gateway in the listing, for the that I had been reading it seems that I need the onlink of the version 0.1.2F, the one that I have is 0.1.2.
In the uplink I didn't have problems to add the gateways.

Kinda messy looking

Also non functional. You can't just ignore the sizes of the gateway components.

For starters, memory sticks are vertical, not horizontal. I could list everything that's wrong with it, but I'll just say that everything is, indeed, wrong with it as far as component sizes.

Might want to try out clipping paths while you're at it.

And for the sake of common sense, you might want to use one graphic for each different component. Ex: Two of your cpus don't match the other 6, and 8 of your memory sticks don't match the other 24.

EDIT: And you probably shouldn't just be taking images of the web and throwing them on a green background.