Hello. 1. This hasn't been implemented in st. It is by design. It's not impossible to implement. If someone has a patch for this I'd be interested.
2. That is by design no need to rephrase it here look at dwm's project page. There's a patch for that. 3. Not using the latest st at the moment, therefore I can't comment on this. However I recall there being a huge discussion on this list regarding the delete key -- if that helps...
