The wiki says your new tie paradigm sysvar .tieangle is a read sysvar. Am I right in thinking that it will change the angle of a tie when you write to it?
Nope. I'm not sure of the exact mechanics, but in order to change the angle
between[ ties you'll need to use another command I'm still figuring out. Basically I'm trying to get it to work like muscles in the human body do, with ties being the bone.
To change the angle between a bot and a tie, you'd just need to unlock the bot, and the bot can swivel like a ball bearing.
The swimming routine in 2.4 was never ported. It's commented out and still uses 2.36 physics. No acceleration forces are calculated in 2.4 due to tie actions on a fluid medium.
I noticed this in the source long ago and it's been on my list to port, but never high enough.
I could never figure out the real life math. The way 2.37 handles swimming forces has some issues I'm not happy with. If you check that New Tie Paradigm page on the wiki you can see my best current guess. Sprotiel, I believe, thought I had it wrong and presents another method. They're not directly comparable, however, as we make different base assumptions (mine being more general).