Stickman's head doesn't collide with anything, that's deliberate. However, the entire stickman going through solids is a glitch, don't rely on it working in the future. Stickman doesn't interpolate like particles do to check for obstacles, so it can go through solids that are several pixels thick if it's moving fast enough.
I don't think that's intentional either. I suspect it is caused by the stickman's feet going inside a wall temporarily, since checking for obstacles to jump off happens after new leg positions are calculated but before collision detection and moving legs away from obstacles occurs.
By wall jumping I mean using the default solid wall and somehow being able to jump off it by pushing into it I think it's a useful feature because by making a narrow column you can jump to the top
Oh yeah I forgot to talk about SWCH. I have a suggestion. My suggestion is that if SWCH has its tmp=1 then its being on or off inverts. It still 'conducts' its life variable to ordinary SWCH and vice versa but if tmp=1 then the SWCH is SPRKable and allows BRAY to pass through on life=0 and blocks those on life=10 Maybe it has a slightly different color too? One major use would be major shrinking of electronics that use combined SWCH where one SWCH is the opposite state of the other. It would also be nice in making an ARAY addressing unit because then you only have to have one row of SWCH for each bit and each row could be a solid row instead of having gaps in between for the SWCH that doesn't do anything, it just spreads the status.