[CentOS] kickstart problems...

Hi,

I am creating CentOS install usb keys and, apart from a few problems, it mostly works...
1. OT: My server HP does not seem to want to boot on it if I set the write protection on.
2. Anaconda tries to fetch the ks.cfg too early...  It detects sda, then detects the 
   RAID adapter, then re-detects sda with a "waiting for device to settle before scanning".
   Anaconda tries to access the ks.cfg file in the middle of this waiting.
   If, once the detection is over (just 2-3 seconds later), I retry, it works.
3. Error message "cannot mount read/write, will mount read-only" (I like to write protect)
4. OT: fs corruption ont he USB keys...
   I copy the iso file on the key (no error message), then compare it to the original and 
   some random differences appear. I noticed in the logs:
   "ext2_new_block: Allocating block in system zone - block = 65536"
   "ext2_free_blocks: bit already cleared for block 88678"
   "ext2_free_blocks: Freeing blocks not in datazone - block = 3003818537, count = 1"
Any idea how to fix 2. and 3. ?

Thx,
JD