increasing humble bundle order

you can check in on your librabry if im not mistaken

Yes, you'll get it.
Just pay attention: the system will ask : how much money do you want to ADD to the current amount. ( Not the 'how much will it be at the end' , as for me and some other players would be logical)
EDIT: I think you can raise the value of past bundles, but only adding more money into ongoing ones will unlock extra games. (Dunno if this is the issue or not, better be safe)

Yes, it does. It should tell you exactly how much you have to add to get to bta.

brilliant, thanks, i bought the bta and now i wanted to get merccenary kings too, but wasn't sure how it'd work out
cheers