Hello Krastor!

I just finished K2 and wanna talk about nice Endgame mod Space Exploration

Fuel Refinery (Important)
I found that K2 Fuel Refinery replaced SE Fuel Refinery and while you on starting planet - everything is ok
But K2 Fuel Refinery is can't be built on space platform and asteroids - it's pretty bad, because you can't craft liquid fuel for fuel your rocket and spaceship. (However the small workaround is fuel them with liquid fuel barrels, but you need tons of them and it's very hard)

White science (Suggesting)
SE has very specific and interesting limitation - you can fly to space with blue science, but White science research can be performed only in Space (space lab can't be built on planets and moons). And it forces you to setup Space Platform, research and resources to space delivery. What the profit? Beacon! This technology need white science. And other top-notch research also. With Singularity lab you can research everything (except really SE related things) on your starting planet.

Space buildings & Beacons. (Suggesting)
In space you have all new powerful buildings, which should be placed in space. They has good speed bonuses and beacons are prohibited in space (Vanilla beacon is prohibited, but singularity one is allowed somehow)

Matter & Resources (Information)
K2 Matter processing is great and available on planets/moons only.
So It's nice, matter processing in space will make game much easier.
Space mining in SE is very expensive, so firstly you have to deliver resources from you home planet.
Main headache with liquids - water and oil. Barrels are very small, each launch is expensive, rocket reusability tech is extremely expensive. Next step is deliver water ice and methane ice from asteroids. It's nice quest and cube->matter->water/oil will reduce complexity simnifically. However minerals can be extracted in space and transforming them to matter can make sence

Energy.(Information)
Now it's casual and simple Coal->Coke->DT->Antimatter.
With single SE it more complex. (coal->nuclear (20-40 cores)->solar in space(long time)->advanced solar in space(very long time)->antimatter)
Seems like it's side effect of paragraph about White Science.

Finally:
K2+SE=already a good compatibility, but we can do It better :)
I will glad to answer on additional questions

and I forgot about sand/glass production - Crusher can't be placed in space (and Matter Assembler).
SE had recipe for assemblers (stone->sand) and Space smelter

electrolysis plant can't be built in Space, so chlorine is unavailable, and rare metals can't be mined (luckily they are not massively needed).

Immersite can be extracted in space(Quarry drill is placable), but can't be used (nitric acid require nitrogen, as we know is no air in space) and cant be converted to matter

Oh, you always forget about Linver. In truth, K2 should be called Linvertorio, since I basically only do graphics. And I can’t start the SE and K2 mods at the same time, since I have a shitty PC. Linver made almost all code and ALL compatibility. So all thanks and questions about SE compatibility to Linver.

Oh, ok
How to connect directly to Linver?

K2+SE is playable, but pretty hard without fuel and sand production in space (new fuel refinery and crusher are not placable in space)

I'm pretty sure that he will read this post :)

Has the Fuel Refinery been fixed yet for SE, so that it can be placed in space?

nope

however K2+SE is playable!

you have to import
- Liquid rocket fuel in barrels (no fuel refinery in space)
- glass (no crusher in space)
- circuits (no wood, quartz and silicon production in space)
- inserters, roboports
- lvl3 modules
- antimatter fuel, nuclear fuel (for trains)

and you have a few bonuses:
+ singularity beacons in space
+ nice inserters, roboports
+ easy and cheap electricity (its 10x great when you build space platform on Asteroid Belt/Field)
+ with increased Solid Rocket Fuel stack size I can just deliver it to far planets instead of in-place production

Hi,
I've just researched Optimiztaion tech (new ++ card) and most of the techs now require: red(automation), green(logistic), blue(chemical) and this new optimization card. However Singularity lab do not accept red, green, blue...
From what I can see those not reserchable technologies have only SE as a mod in description. Bug?

Example "not working" techs: Space Assembling, Recycling Facility...

There are some tech that have correct formulas, like "Mattet tech card", but all SE techs are now out of reach....

What I'm doing wrong?

just fly to Space and setup Space Lab - it accept all cards

anyway almost all space buildings should be placed only in space