[Nexus S General] niiiiick:
It works! Thanks a lot, very helpful guide. I have a few quick questions though:

- Right now my phone is rooted and has SuperUser installed. I checked through Root Check Basic that I'm rooted and it confirmed it. I didn't understand your steps to make sure Clockwork isn't removed though and I skipped them, so now it's gone. If I simply flash Clockwork again, will I lose my data and have to re-flash ICS?

- Will I get OTA updates given that it's still essentially a stock ROM? I don't mind losing root as the only reason I rooted is to get ICS.

Thanks again!

A few comments for other readers considering this guide

I'm a noob, and I know it. These are comments so any other noobs reading through this thread or Googling the problems I had finds what they were looking for. I'm not criticizing your guide in any way as I know there's a basic expectation of competency on xda and you still went far beyond that and did a great job holding my hand through all the steps. I assume some/most of these comments are obvious to people who actually know what they're doing, but here goes for the other nooblets:

- As someone said previously, it seems you need a new version of Clockwork Recovery. The original guide I used to root my phone installed Clockwork 3.0.1.0 (I think?) and it didn't work. I also had other problems (see below) which only popped up after I installed Clockwork 5.0.2.0, so it's possible that it isn't necessary, but always go for the newer version, I guess. You can flash a new version of Clockwork the exact same way you flashed the older one (I actually repeated the steps in my rooting guide but I swapped the old recovery file with the new one)

- Make sure you back your stuff up first, including a list of all the apps you had installed if you think you might forget. Google didn't reinstall my apps at all despite my having repeatedly checked that backing up to Google was selected in my settings in Gingerbread. The Market remembered the ones I paid for, but I had to log into the Market on my PC to see the free ones to reinstall them. Even then, some were missing and I couldn't find the pattern as to why. This could be my bad as I probably rooted and unrooted and flashed about 5 different ROMS trying to figure everything out last night, but better safe than sorry.

- I initially had a problem installing ZD3PyN0t.zip. It would start opening, then abort and give some kind of error message like "cannot open (BAD) - aborted" and then all I could do was enter (power+volume up) mode. Eventually I figured out that somehow the original "ZD3PyN0t.zip" that I downloaded was corrupted and I couldn't even open it on my PC to explore the files inside. Redownloading it and resending it to my phone via "Mount USB storage" in Clockwork Recovery fixed it. I have no idea how it got corrupted, but if you're getting that error message just delete it and re-download. You can check if it's corrupted the same way mine was by trying to explore the files in the .zip from your computer.

- I didn't need to go through the 3G network settings for some reason. The only network it could find was Telus, which it automatically understood as Koodo and worked immediately. I didn't have the same menu options available to me as OP listed, but in the end it worked. Maybe it's because I left my SIM card in the phone the whole time? I'll never know, point is it worked, so I'm not complaining. So I guess give 3G a try before you tinker with the advanced settings and so on. Keep the settings OP suggested on a file in your phone so that if your 3G ever stops working you can easily configure it on the go. [SEE EDIT]

p.s. for anyone who cares, I'm running a Nexus S I9020A on Koodo in Montreal. Battery life and performance so far seem excellent, although I've been using my phone constantly so I haven't been able to check standby battery life yet. Right now I'd say I'm looking at a total "screen on" time of about 5-7 hours, which is slightly better than I was getting on stock 2.3.6. I'll report back if I have battery problems, but so far it doesn't seem like it.

EDIT: 2 things now that I've been using ICS for a few days.

- Battery life is AWESOME. ICS seems to be better at stopping my phone from being "awake" so much when the screen is off. Battery life during heavy use is slightly better than Gingerbread, but during light use it must be doubled or tripled (i.e.: on pace for many days of on-time, whereas I used to be lucky to get 18-20 hours with Gingerbread even on what I would consider a light day).

- I had some trouble setting up my APN settings right. I was having trouble downloading from the Market and a few sites over 3G, but everything else seemed to work (I'd browse to an app in the Market, click download, and it wouldn't start. Then I'd get "app name" could not be downloaded due to an error. I fixed it by deleting the "Proxy" and "Port" settings from my APN. Credit goes to this thread I found:

So, settings that seem to work:

APN: sp.koodo.com

Proxy: [not set]

Port: [not set]

Username: [not set]

Password: [not set]

Server: 74.49.0.18

MMS Port: 80

MCC: 302

MNC: 220

Authentication type: [not set]

APN type: [not set]

APN Protocol: IPv4

Bearer: [unspecified]