i have 4 question about server and attachment

[fariborz khan]

hi
i have 4 question and i ask you answer by number :
1.can i open multi rar archive file that have password in my host or are there any script that work like winrar in a site or server side
2.i want only my vbulletin users can use my other site files (that hostet to other server)....or....can i share my user between two site...for example only people that register to my vb forum can login to my other site and use it.....or....how can we share user between vbulletin and a downloud site (that thay have different server)
3.can i upload or attach rar file as image in photo post pro
4.i want a download II like hack that use database for store file like vbulletin (that store attchfile in a attachment folderin *.attach format)
thanks alot