The Scavenger is indeed supposed to drain food to attack with some abilities, much like other abilities drain energy.
To make the necessary power units for constructing anything with immense energy requirements, one needs Power Prism Crystals and Fuel Converters.
The Advanced Exoskeleton does upgrade more, but to upgrade it all the way, you'll need more than just basic armour plating.
The Timer is a bar, by the way, and the script to reduce it is clearly marked.
On low health, you will drain food faster. Much like real life, wandering around with a gaping hole in your chest will sap your energy faster than it would if you stopped to plug it up. This makes it more in one's interests to save health packs until you're low on health, rather than just keeping yourself topped up.
This does, admittedly, make the game slightly less forgiving in certain circumstances.
To offset this, I might combine the low health food drain with slow regeneration to a minimum level of health at a later date.
Humans gaining abilities automatically was implemented in the original Werivar mod long before I involved myself in making the expansion. Now, the human gains automatic improvements with level, rather than being able to pick the best abilities straight away.
Metal tube is, last I recall, still on the same map it is in Basic Notrium. Double barrel shotguns can be made by.... adding an extra barrel, curiously enough, whilst the laser rifle's barrel needs to be added to something a little more potent than the laser pistol.
And, as I'm still busy with other things in life that prevent me from doing the more entertaining things like scouring through buggy code.... I guess that's all. Ta ta.
haha thanks for all the info, i just still cant find that code >_< and i found out the prism thing cause i just placed a powered ether generator down somewhere and when i picked it up it said "after adding the power prism crystal" etc. last i recall there is a double barrel shotty in the cave at the gorge no clue what to do bout the laser rifle though, im gonna try messing with a sniper pistol or something, maybe the rapid laser pistol thingy (forgot the real name haha (im a loser!!)) oh, and i searched for the metal tube in the editor but i couldnt find it anywhere in the gorge maybe it was accidentally deleted?
oh and sorry if its hard to read, didnt think about putting spaces between the stuff