upgrading the xda2 to wm5 questions

[fvig2001]

Hi, my brother is getting his xda 2 back and has asked me to install wm5 in it.
My questions are:
1. Do i need to simunlock his phone first, his phone is locked to smart philippines?
2. Is there anyway to backup his original rom, so i can flash it back in case he wants to downgrade back?
3. does upgrading your phone to wm5, simlock the phone again?
4 .Is it true that wm5 has problems regarding pocketie, camera button and loss of camera resolution?
Thanks in advance

[Rudegar]

1/3 roms and simlocks are never connected what so ever
changing rom will not sim lock or unlock (unless a tool to do so is autoloaded)

2 not sure what ppl mean if you have rom 1.72 and install 2005 and then install a 1.72 again you are back to your own rom not sure why one would want to backup the rom one had rather then just installing the same version again...
but if you mean your data then you can just use xbackup or spirite backup or activesync backup and restore that backup when you revert back to the rom version you had first.

4 if you read it in the 2005 forum and ppl dont have a fix you can find using search function then i guess so.

[fvig2001]

2. I wanted to restore the original rom, as in the rom itself. Just to be on the safe side.

[Rudegar]

the rom on your device is == 100% the same as the same rom version from the same operator's install files for that rom

so if you have 1.72 from tmobile and install 2005 and then get tmobiles install files for 1.72 and install that you have 100% the same device
with digital things everything is 0's and 1's
so there cant! be any difference between the rom from tmobile 1.72 you have and if you install 1.72 rom from tmobile
there is no hardcoded stuff which makes the rom of your device uniqe compared to every other device with the same rom

everything you need to know
http://wiki.xda-developers.com/index.php?pagename=Himalaya
http://en.pdamobiz.com/en/forum/forum_posts.asp?TID=62