I do a ctrl + left click drag on all my furnaces, a little bubble shots up on them to show how much is going to be put into the furnaces, and then either i let go or it times out, but either way, it puts ZERO into the furnaces, and dumps an entire stack into the first furnace i clicked on.

Not sure if this is an unintended behaviour with another mod

Edit: Its not the furnaces that are broken. its the labs. It works fine on furnaces, but not on labs.
Edit2: It seems to attempt to put an entire 200 stack into the first lab, and spread the remaining science packs over the other labs.