More upside down mapping questions!

[Sere]

Ok, I've got some more questions about trick jumps that are possible while up-side down.
Can you ctap from a ceiling?
Can you bounce from a ceiling? Uncrouched at least?
Can you edgebug/edgeshot upside-down?
Can you downpogo(well, technically it would be up-pogo )up-side down. I wouldn't probably make something that evil, but I just want to know if it is possible?

[Dr. Heinz]

edgebug is possible, I am pretty sure I did it once on jump_drexen2 on the reversed gravity jump.

[Grandpa]

No.
Yes.
Yes.
Yes, but its gonna be a piece of shit to get right.