Check if your Starting Tech is lower than 3. Many, as I myself have done so, sets the game believing that the Starting Tech Level has anything to do with tech progression in this mod, but in fact, it doesn't. Regardless of the Starting Tech Level (that you choose when setting up the GC campaign) you set, you always start the game at Tech Level 0 and must build the Tech Level Space Stations. Nonetheless, if your Starting Tech is lower than 3, most units will be left out of your game.

TL;DR: start a new GC campaign with the Starting Tech Level set as at least 3, and all units and heroes will be available to you.

At the beginning, I could build several different SD's, but at one point the option to build them just disappeared. I startet at Tech 0; as if teching up deleted them.

Originally posted by Tavaron:

At the beginning, I could build several different SD's, but at one point the option to build them just disappeared. I startet at Tech 0; as if teching up deleted them.

did u press a filter

Did you fail a KDY mission?

Double nope.
I just started a new game. Let's see if it happens again.

What excetnsion you have? Super ship or fighter? Super ship buildable only when you have level 3

Oh of course. You have built extensions to your shipyards, which allows you to build different ships but doesn't allow you to build the original ships as well. Nothing to do with teching up, if you build another cap shipyard or downgrade the extension you can build them again.

ive had this problem as well and it wasnt due to the shipyards. It happened in almost all of my campaigns with the empire. It removed the options for almost all capitalships and i couldnt fix it even by rebuidling all my shipyards or clicking on any possible combination of the filters or doing missions or anything really.

I had this same problem on my first imperial campaign. I love this mod (it's my first), but I lost all ability to do space production as the empire several turns into my playthrough. I've switched to the Rebellion for a new campaign and so far so good, but I'd love to know how to fix this in case I play Empire again and it happens.

Again, did you fail a KDY mission?

Originally posted by General Brooks:

Again, did you fail a KDY mission?

does that take away your ability to build star destroyers?

It takes it away for a while yes.

Someone decided to dedust this old thread. :D

Originally posted by General Brooks:

It takes it away for a while yes.

good to know. thanks.

Originally posted by Tavaron:

Someone decided to dedust this old thread. :D

well i was having this issue and was wondering why.