Yes, the plug inside the robot connects to the existing interface. Yes, if the player selects an item in the crafting view, that would alter the selected item for that robot. Yes, this will simplify the "manual" method of creating desired sensors.
While I have some debug switches I can flip to help me with development, I'm not too keen on creating features that are not intended for final-game use. While I fully support the idea of "code to assist QA in doing its job", I'm just a one-man shop, and I really need to focus on getting the game to playable/shippable! I don't mean to seem overly bureaucratic about it but, for now, it works best for me if beta-testers report bugs (as you have been) and I use my tools to track them down (as I have been.) Thanks!
That said, I think most of what you asked for as QA-features is planned as actual features, so we're good, there!

Each robot =does= have a separate crafting (and market) interface, to go with their individual inventories. Currently, the "out in the farm" buttons default to your first robot. When we get later in beta, I may remove those buttons as ambiguous, since they really belong to the individual robots.
If one robot has 1/2 the mats needed to craft something, and another robot has the other 1/2, neither of them can craft until they work out how to transfer mats between them. "Chop-chop!"

Similarly, individual robots buy/sell things at market. Robot#1 can't sell robot#2's goods and robot#3 can't buy items on behalf of robot#4.
I understand that there was some confusion early on, as "inventory" was presented as "player" inventory. It is really "robot" inventory.
A key concept of the game is:
The player doesn't do things. The player programs robots to do things. 
Posted by WORFC, board admin, moderator, game author.
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