Marketfix: not manadatory.
copy of what market fix does from sapphire wiki:
This release of sapphire updates its build.prop information to reflect the FRF84B OTA leak from Verizon. This means that so far as the market can tell, your device will be an Android 2.2 (Froyo) phone running sholes (Droid) hardware from Verizon. This generally works fine, but there is an issue on market where some paid apps do not show up on 2.2. This is most likely an issue with them being flagged as incompatible with 2.2 as they haven't been updated, or some other such thing.
In response to this, I have made a market hack that will essentially “trick” the market into thinking your device is an Android 2.1-update1 (Eclair) phone running sholes (Droid) hardware from Verizon. This essentially allows the device to browse market, but has the potential to have adverse effects, as the market no longer knows the real version of the operating system, and will make decisions based on that false information.
In the end, it is up to you to decide whether or not you wish to apply this patch or not. There is no real danger in applying, nor in not applying. I recommend making a backup anyway. Also, I have not tested what happens if this patch is applied prior to the initial boot of the system, so I cannot say whether market sync will function properly or not. My recommendation is to boot without the patch, wait for your apps to finish syncing, and then apply the patch if you wish to.
Thank you for reading my explanation, and as promised, here is the patch file:
Download
sapphire-0.8.4-market_hack-update.zip
To install the market fix:
1) mount droid
2) delete update file on sdcard
3) install the marketfix update.zip to root of your sdcard
4) right click file and rename to update.zip (update for windows 7)
5) reboot into recovery
6)
Make a nandroid back up
7) allow update
8) install update
9)
wipe cache only
10) reboot
11) enjoy all your apps.
12) later I would recommend installind titanium back up and backing up your apps, save you time when it comes to restoring apps and apps settings.