:
1) Impossible, Even the best speed runners around can't get that i don't think
2) Impossible???
3) Possible
4) Possible, Quite easy too 
5) Possible and really fun to do. |
By 'Stockyards', I meant the first six screens with RuptureFarms flooring, not up to the part where Abe falls down the cliff. Which is possible if you look at people's times on YouTube.
And I'm pretty sure there is a point in FeeCo Depot where there are many mudokons on one screen where if you slap one, it will cause a chain reaction where they will all start slapping each other and die. I don't know if it is as many as twelve though.