I'll be honest if you don't mind; i find this to be sooooo complex already that i doubt i would even try playing a game with that much new Macro-Managing to do -- but, that's only me, others may differ!

As for the cap on the number of Techs... X-Worlds does have a whole bunch of new techs also but not nearly as extensive as yours has become.

Even your xml listing in the other thread couldn't keep up or fit my browser scroll frames (and it IS a top-notch Mozilla with some personal enhancements patched in, btw)... so, that begs a concern for extending that much items on any given customized version(s).

I'm not sure if there is actually a true maximum of valid assets (techs or not) the game engine can handle; logic dictates there HAS to be one, of course (Local RAM being just one). Carielf could probably give you the exact numbers... but, lately i think SD coding staff has been very busy on other priorities such as fixing some TA issues and working at the double adapt version 1.92 for DA&TA.

I'd recommend grouping (or a thorough re-design) even further if you'd still wish to
keep it all as it is... unless, the implied Cap was indeed reached.

This is what my techtree looks now:




How I made this?
I don't think there is a real limit of techs, the problem is the file size. Normal techtrees are somewhat about 50KB, but mine was about 150KB, which is just too much for the game. I've just deleted some useless lines in the file and then it was just 90KB big.
I think the maximum file size is between 130 and 140KB, and my techtree has got 133KB now.
I don't think I will add any more techs, I'm more than satisfied with the techtree as it is

They are not really useless, but they are not very important.
I mean lines like "Willingness to trade" or "Can be stolen" and so on.

Hmm, you're right there.
But why is my techtree working now? I'm sure it was no typo or whatever, because the only thing I did was deleting some lines, and an eventuall typo should still be there.
And when my techtree was 150KB big, I could add as many techs as I want in the editor (so a typo is not possible) but those techs didn't show up ingame.

Ok, the lines I have deleted are important, but not to me. I usually play with tech-trade and tech-stealing off, so I don't need these lines at all

Now I would really like to know what prevented the techs from showing up ingame.
A limit of techs? Can't be, because now I have even more techs.
A limit in file size? Also not possible because of what you said Zyxpsilon.
But what is it then? Maybe one of the devs knows it, who knows?

Is there any way to show the tech tree in the tech editor the way it is shown in the game?

@di55ec7ion

Nein, kann man nicht

@Gizmo... i am 99.9999999999999999-infinity% sure here, too!

The only way to find the exact line that caused the problem is to go back to the non-working techtree, then deleted line for line and check after each line if the problem has gone away.

Or does the debug.err show errors in the techtree?

Well, one can't really see anything. Make more partial screens instead, zoomed in of course.

Best practice to eliminate the error is, comment out the differnt branches eg first the diplo ones then biology, computing etc. you got to shorten the techtree to have any chance of finding the nasty creep.
I had this once, and it worked out quickly that way.
The problem comes from editing the techtre by hand eg renaming the tech_id and then loading it into the editor. the editor can't recognize the change and assigns somehow the next higher! tech for techrequirement, which is simply not researched yet. This produces the crash. So you "only" got to check the techrequirements
Do not load the tree with the comments into the editor, since it tends to dislike comments and deletes them (
Better edit the whole tree by hand and just use the editor for finetuning