Ok, finally all the roms and such are aquired, so i went on to fix al lthe chd errors (the one "you should update" error message)
Fixed em all except for the area51 one

i get this error message :
Area 51 (Nov 15, 1995) [folder: area51]
wrong chd sha1: area51.chd [wrong: no SHA1 set | better convert chd to new standard] [right: 9ea749404c9a5d44f407cdb8803293ec0d61410d]

so i asked what do do with this and was told to use chdman to combine the area51.chd file (560 425 712 bytes) with this 10 mb file to get a new area51.chd file (546 424 630 bytes) and now i get this error :
Area 51 (Nov 15, 1995) [folder: area51]
wrong chd sha1: area51.chd [wrong: fee528eef8a256f87af299499ecf5817218f5202] [right: 9ea749404c9a5d44f407cdb8803293ec0d61410d]
wrong chd md5: area51.chd [wrong: 60d051da941d76aafd47c862e3b6e209] [right: 130b330eff59403f8fc3433ff501852b]


whats going on here ?