space channel 5 part 2 problem

[chph]

i haev a problem with space channel 5 part 2
I downloaded all the files.
they are all named "DC_SP5P2_Jap.part1.rar, .part2.rar ...
when i tried extracting from the first volume: DC_SP5P2_Jap.part01.rar it tells me 2 things:

! C:\WINDOWS\TEMP\DC_SP5P2_Jap.part01.rar: Unknown method in DC_SP5P2_Jap.cdi
! C:\WINDOWS\TEMP\DC_SP5P2_Jap.part02.rar: You need to start extraction from a previous volume to unpack ....
its logic that it deosn't extract since all the 29 filez finish with rar and not r00 or 001, 002...
but i can't find out how to rename them or how to change the method in DC_SP5P@_Jap.cdi
Please help

thx