1) & 2) are obvious.For each of the following questions that you can answer with a “yes”, you get one XP:
1) Did you participate in the session? (You getone XP just for being there.)
2) Did you perform a Day’s Work for a project inthe Ark (page 103)?
3) Did you explore at least one new sector in the Zone?
4) Did you sacrifice or risk something for your PC buddy (page 22)?
5) Did you sacrifice or risk something for the NPC you want to keep safe?
6) Did you sacrifice or risk something to mess with the NPC you hate?
7) Did you sacrifice or risk something to reach your big dream?
3) - Does scouting from a lookout point counts as exploring (according to p.122 - yes) in this case? Does every explored sector count as a separate XP or do you get only 1 XP, even when you explore (with or without a lookout point) multiple sectors? When a stalker "explores" a sector from a lookout point, do all PCs gain XP for this or only the stalker does?
4)-7) - Could you give some examples? Does giving grub/water/bullets/gear to a buddy counts? How can you risk/sacrifice something for a NPC never leaving the Ark, when he's not in danger? When you have a NPC you hate what do you do? Do you deliberately find him in the Ark and start a fight? In my opinion it's just XP-grinding, not roleplaying. How can you risk/sacrifice something to reach your big dream like "find Eden" or "find something to die for"?