Hi and sorry that it has taken so long for me to reply.
The way to install Win7 and MAC OSX on the same HDD is this:
1.0 Boot up SL installation
1.1 Open DiskUtility and make (at least) two partitions
1. for MAC OSX
2. for MAC OSX BACKUP (optional but highly recommended)
3. for WIN7 (FAT)
I advise you to name the partitions just like this. It helps identifying them later.
1.2 Install MAC OSX and make it bootable and fully functional
2.0 Boot Windows 7 installation
2.1 Choose custom installation
2.2 reformat the WIN7 (FAT) partition to NTFS
2.3 Install Windows 7 on it
3.0 Boot SL up using iBoot
3.1 In terminal type this:
sudo -s
(enter the admin password when asked)
fdisk -e /dev/rdiskX
(X=the number of the SL installation disk, (use DiskUtility to find it out) )
flag Y
(Y=the number of SL installation partition (use DiskUtility again) )
write
exit
4.0 Install Chameleon RC5 bootloader (again)
Now you should be able to boot up Windows trough the Chameleon bootloader.
The reason for a backup partition is that sometimes you can't start up MAC OSX partition any more after installing Windows but the backup partition boots just fine. Installing Chameleon on the backup partition works just fine too.
This way worked for me just perfect. If you get stucked or get fried just make a post.