Yes, Red Hot Blue Glue is the best... but really TRY and make all the surfaces as dry as possible. This product has SAVED me time and time again and I use it for all applicable projects, regardless of "dampness".
Must be done right away in order for it to bond. Once you apply the cement you must give the bonded parts a little twist. Hope this helps.
No. Its not expensive. Buy new fresh glue!
Yes, they are attached to the lids.
Cannot say as the size of the pipe fittings matter.
I keep mine in a air tight sealed container. The ones used for cereal and such. Kept my floors from drying out. Works on all sealants to be honest. HTH
Yes it will. It does look a bit ugly. Clashing with the gray color.
It depends on outside temperature, pipe diameter, and water pressure. See handy chart directly from Christy’s: https://tchristy.com/wp-content/pdf/howto/Set%20and%20Cure%20Times%20Guide.pdf