[Galaxy S I9000 Android Development] yani2000:
Hi! It's me again...

This time with more news!

I knew going from custom official ROMs to a AOSP one or CM one would be a pain, but I didn't imagine it would be so bad:

O....M....G !!!!1one

You had an issue in this ROM?

I had them ALL!

Point 0: First I had to get from a clean stock Samsung ROM (like latest Open Europe one: I9000XWJVZ_I9000OXAJVT_OXA).

Flash it in Odin with all options checked except Flash Lock & EFS Clear.

Then in EZOdin I had to flash EZboot-GingerBread-1.0.tar with Bootloader update checked to it can flash boot.img that's included in that tar file.

I tried flashing Semaphore ICS kernel from CWM v2 and it was a no-go, back to EZOdin now with Bootloader update not checked (because Semaphore kernel doesn't include a "boot.img" file, only zImage (kernel)).

Now the pain begins:

1. issue: I had no modem, flashed JW4 and 3G starts working. Yeah! Tried TWICS and found out it was a Joke! Only Launcher and some unimportant stuff was ported. I really wished for a TW Phone port with that nice left/right swype to call/SMS a person. Oh well... back to point 0 for me! Oh, I also had a WiFi disconnection issue, reboot solved it!

2. I had done exactly the same as before but this time I had a fake IMEI (the one ending with "0000") and my 3G data wasn't working. Copied "nv_data.bin" from my backup to /efs folder restarted and still no-go because now I had IMEI SV set to 03 and I remembered that it was always 01. I tried various things for several hours, ignoring IMEI SV set to 03 and thinking it was an APN issue, because my carrier is so stupid that doesn't even know what their correct APN configuration is. Anyway, back to point 0 for me!

3. Done exactly the same as before, first boot greets me with: Encryption Unsuccessful, pressed "Reset phone" because I had no personal data and had a full backup on my PC. Phone resets everything was normal.

Flashed JW4, had again fake IMEI and no baseband was shown, 3G data was working. Restored "nv_data.bin" with the SAME bacup as I had before and now I had right IMEI and IMEI SV was also 01, yay! Ah the WiFi disconnection issue reappeared, reboot again sloved it.

Flashed Semaphore ICS kernel and noticed NSTools and Update Me were missing (both were in slim_common.zip/data/app).

Reinstall of both apks solved it!

4. Started installing apps from my Titanium Backup and hit a "Low Storage" notification. At first I was WTF and didn't know what was wrong. Found out I need to make a .nodadadata file on /datadata, reboot and in CWM format /datadata.

Guess at this point not entire /datadata was moved to /data/data and I deleted some database files with that format. Back to point 0 for me! Yay! :/

5. At this point I made 100% sure that only "lost+found" folder was in /datadata before I formated it.

Now I had everything stored on /data/data and I would kill anybody that said there are no severe lag issues with this approach.

It felt I was back on stock Samsung eclair v2.1 ROM.

Everything was working "fine" (minus the lag) and I wanted to get rid of the lag with some nice fixes (like Datafix app from Play Store). It was suggested that I make a nandroid backup before I start and I did. I did just that, nothing else, honest! CWM --> Backup and Restore --> Backup

After reboot my CPU started acting up with constant 100% usage. Found out on XDA that I had to clear data for "Download Manager". I had to do that for every restart or if the Media Scanner was initiated (with a file change). Or I need to kill "Downloads", that would also bring my CPU back to normal.

Also, at some point in CWM I tried to Clear cache & dalvik only that two, nothing else, honest! What I got in response? Bootloops! Thx god I had a nandroid backup handy that I made before.

Now, I have everything working except for an app acting up (same stupid app crashed going from froyo to GB).

It wakes up my phone thru LocationManagerService.

And I have also found out that "S30datafix_ng_busybox" doesn't start in /etc/init.d, I have to manually start it thru a script manager or terminal emulator in order to work.

So I had them all: WiFi disconnection issue, fake IMEI issue, Encryption Unsuccessful issue, Media Process issue.

The thing was that I knew I needed to update my OS and I knew an ICS ROM was the best option, because all devs are working on JB ROMS. Problem is this is a never-ending cycle and the "fast" Android updates are killing developement because every previous ROM is stopped being developed at some point and some issues remain. In result, we get a 90% working ROM. :/

At least I'm a power user and I searched XDA or tried to fix problems myself. Now almost everything works as it should and I must add that I once had a 1% battery drop in 6h when I was sleeping (wifi+sync on).

And I really liked Slim ICS otherwise I would give up and go back to stable SURFACE GB ROM.

At least we have hard working devs like krarvind that need to recompile ROMs from AOSP source (from scratch) and tweak it, no thanks to Samsung that gave up on this phone long ago.

If it were me I would use a custom Odexed Samsung ICS ROM, but as I said it before, that is not an option.

Good luck and I hope that if you encountered an error that my post will help with fixing it.