Steam won't accept my terrain shader mod for 0.990, so here it is for now:
It is in a zip file. Extract to your SpaceEngine>Addons folder, usually Steam>SteamApps>Common>SpaceEngine>Addons
UPDATE: RM.pak no longer works in the latest versions, as such is as been removed. The above file will remain for posterity for older releases of SE Steam. Now, just copy the .pak below into Steam>SteamApps>Common>SpaceEngine>Addons, that's it.
BE SURE TO DELETE THE CACHE FOLDER AFTER UPDATING OR INSTALLING!
Specs: STGAubron desktop PC; NVIDIA GeForce RTX 3060/PCIe/SSE2 12 GB Vram, Intel Core i7-8700 3.2 GHz, 12 cpus; 32 GB RAM; Windows 11 x64