Ok, thanks! What do you mean by (winning path) if I play other paths it doesn't work?
I have no idea what he means with "winning path" either. The campaigns are linear with no separate paths. It's been awhile since I played them, but from what I remember, the bug in the Dread Lords-campaign should be fixed.
Still, it might be better if you play the older campaigns with the games they were made for. Certain game changes in Twilight of the Arnor make the Dread Lords campaign much, much more difficult, for example. Plus, there are techs, that serve no purpose in DL, like Asteroid Mining and Extreme Colonization. The Ultimate Edition has sadly no easy way to access the older games, so you would have to do it manually. You can find the exe for DL (GalCive2.exe) in the main game folder and the exe for DA (GC2DarkAvatar.exe) in the DarkAvatar sub-folder.
I've been reading some more on these forums what do you think about the whole thing about 'Twilight' being broken? I've only played 1 game but haven't noticed other civs not building planetary improvements etc. albeit this was on a small map.
I don't think, that TA is "broken". Certain AIs have some problems and there are bugs in the tech trees, preventing the AI from doing a good job, but that doesn't mean, that the game doesn't work at all (which is what "broken" implies). Most of those problems can and have been fixed by us modders, the rest can be circumvented (to a degree).
AI-Personality 7 (Drengin, Korath, Yor) won't colonise outside of its sphere of influence or anywhere where it might be "threatened" by foreign culture. This often leads to them loosing the colony-rush and, eventually, the game. You can circumvent this by making sure, that AIP 7 starts with as many planets in its sphere of influence as possible.
AI-Personality 10 (Torians, Iconians) stops building planetary improvement once it gets a certain amount of colonies. This is only really noticeable on larger galaxies with lots of planets. The number of planets necessary for this to occur is unknown (at least by me), and there is no way to prevent this (except by simply not playing on galaxies larger than small). Due to this, we modders changed the AIP those two races use to either 8 or 11 (depending on the mod). You can easily change this yourself by editing the races in the Opponent Selection screen.
Regarding the bugs in the tech trees, planetary improvements, and so on, you will have to use a mod to fix them. There are four to choose from, each with varying degrees of departure from the regular game. For a new player, however,
APT is probably the best, because it is just a bug fix.