Thanks for the feedback!! let's see
1) the stages you mentioned use the same devices already presented by previous ones, which i think can serve as a hint to what to do. stage 10 has the same terminal as stage 4, stage 11 has the same devices as stage 8 but for a different function, stage 12 mixes stage 3 and stage 11 elements, stage 13 mixes stage 11 elements and the supervisor behavior from stage 10, and stage 14 has stage 7 and stage 1 devices.
2) the stage 3 scene has just a bit to the chest, but don't worry, we'll have ones focused on them!!
3) i checked the sprites but couldn't find it, i think it happens when the screen zooms in
4) if you're having trouble in any stage, you can save anywhere you want inside of them to help a bit ᕙ(‾v‾́)ᕗ