The cost is normal but after the first efficiency tech the cost for all tech is set at the maximum ! nobody can reach fusion...and is useless with the actual tech tree....
I'll eventually make a SE integration (if someone else doesn't make a patch first), but right now i'm focusing on making integrations with Krastorio, bobs and angels.
I don't think you need permission to make a compatibility patch.
One thing though, someone else already messaged me on discord saying they are working on a patch, so you might want to get in contact with them: PeterHan5#1790
I m working fast and the patch could be teminate in some days (include tech tree cost issue solved,recipe immersion with se material and some change To prerequisites techs hierarchy) ^^.
THE other guy don t message me. So i send the patch To Earendel when i end it. ;) i just need To adjust recipe with some of your mod parameters for the final step.