1) Actually, it doesn't require constant chakra emission. You pay for it once, and then it requires a certain level of concentration but no maintenance. This is part of what makes it so suitable for Academy students, but also part of what makes it so fragile.
2) No. You don't have that kind of "pure" chakra manipulation ability. Like most non-Hyūga, you can only emit chakra through your hands and feet, and your ability to do so doesn't have the kind of precision necessary to manipulate a technique not designed for it.
3) No. You don't have any control over the technique once used, except to dispel it by dropping concentration.
4) No. It's a single coherent effect, which is why even the most localised damage will pop it.
5) You don't refresh or stabilise a transformation. Any external effect that targets it, meanwhile, affects the whole thing as a single target (until it pops, at which point the effect targets localised parts of your body as normal).
It should be mentioned that you have not witnessed anyone you recognise as an Aida performing religious duties in the village, or indeed much by way of formal religious rituals taking place.