I am also having this issue think it depends on the type of start, I've been playing with crashed start and its been working fine but did a standing start and now cant research any imperial stuff did you do the same or did you start in drop pods?

Also having this issue any guidance on what we should be doing to ensure its available?

dude iv looked for answers for this for a week just use dev mode and complete the research only solution i could find

or just use grim world if not for sister of battle armor id never use this mod rimdark and grimworld are much better the weapons are actually balanced the ones in here are meh