Right now we can only specify from which slot we pull the items in a inventory and by default the method will push the full slot to the first empty slot in the targeted inventory. But what if I need only one item from the slot? what if I'm using a special storage unit from a mod and it make a difference to which slot the items are getting pushed?

In the existing version of CC:T we don't have a solution to those problems and I don't think it will be hard to implement those.

Hrmr, isn't that the limit argument to pushItems. Or am I misunderstanding what you're asking for?