My phone was working fine, version 1.0.2 (when they were for 699$), my stupid friend upgraded it through itunes to version 1.1.2

now since he did, I tried reinstalling firmwares 1.0.2, 1.1.1 and 1.1.2
NO USE!

I tried everything, Last solution I came up with was returning to 1.0.2 (using iNdependence on mac), with iTunes 7.5, DFU and all. I was able to install 1.0.2

Phone works fine now, everything works fine. but sim can't be unlocked!

Baseband version: 04.02.13_G
Firmware version: iBoot-159
Build Version: 1C28
Jailbroken and SSH installed.

I don't have wi-fi, I tried jailbreakme.com (nothing but that silly tiff shows up).

and whenever I try to install "AppTapp Installer.app" I get an error!
the phone restarts in the yellow icon mode and I get "error: bootstrap failed"

I seriously don't know what to do! and a guy is asking me to pay him 100$ to fix it, he is also not sure if he can fix it!

I'm on mac os x tiger (last version), iTunes 7.5, iNdependence 1.3.1, I keep getting "incorrect SIM" error msg on screen!

I tried the *#310* and 307 methods, downgraded and upgraded with failures 1, 1013 and 1015 many times!

I've been doing that for the past 16 hours! I need help, no wi-fi (I have copies of all firmwares from 1.0.2 to 1.1.2 saved).

HELP!

It is more like an iPod touch now

If you read the guides properly you would realise that errors 1013 and 1015 are expected and can be ignored