The scrapper's Called Shot ability aswell as many enemies apply conditions (such as grappled, blinded, disarmed), though i cant find anything in either of the books about what these do. Have i just missed a piece of detail, or is the GM or table supposed to come up with what the conditions do themselves?

Thanks for playing Lost Eons! Yes, coming from an FKR mindset I wanted to leave the exact meanings of the conditions to the GM, as they will best understand the situation at hand. But my rulings in general would be- 

Grappled- Can’t move until use an action to free themselves in test of Muscle vs Opponent, Soul Dice becomes d4 while grappled. 

Blinded- Counts as Dazed Condition, so Soul Dice becomes d4, disadvantage on actions that require sight. 

Disarmed- lose weapon and any benefits, any attacks and defense rolls are at disadvantage. 

As I say, these are rulings I would use in general, but they could differ in the moment. I hope that answers your question.