[Galaxy Tab Q&A, Help & Troubleshooting] Tony98:
i'm not an english expert, but i'll try to explain you what happened, and i hope you can help me.

i have a samsung galaxy tab gt - p1000, with an old version of android, 2.3.3, because it's one of the devices wich haven't got the update. but i have bought it about 5 months ago, so i didn't want to waste it. so i decided to put in it the new android version ice cream sandwich, 4.0. and i followed theese instructions:

Requirements and Reminders

To be able to flash the MIUI 4 Alpha ROM on your Samsung Galaxy Tab P1000, you need to satisfy the following requirements:

Root your Samsung Galaxy Tab 7″ and install ClockworkMod Recovery on it.

Fully charge your tablet’s battery.

Back up all important files and data on your device ( i.e. bookmarks, contacts, SMS, APNs, etc.).

Download the MIUI 4 Alpha ROM for the Galaxy Tab from here and save the file to your computer.

The procedure has been tested to work on the Galaxy Tab GT-P1000. It may or may not work on other models.

Use the instructions at your own risk. We shall not be held responsible for any damage to your phone if you follow these instructions.

Installation

Here’s how to install MIUI 4 ICS on your Galaxy Tab 7″:

Connect your tablet to your PC.

Copy the MIUI 4 ROM to your device’s internal storage.

Disconnect your tablet from the PC.

Turn off your tablet.

Reboot the Galaxy Tab into ClockworkMod Recovery by holding down the Volume Up key and the Power button simultaneously.

Once the device has booted into ClockworkMod Recovery, create a backup of your currently working ROM. You can do this from thestyle=”font-style: italic;”>Backup and Restore > Backupmenu. This backup will come in handy in case you want to revert to the original ROM of your device.

From the recovery menu, select “Wipe data/ factory reset” and confirm that you want to perform the action.

Select “Wipe Cache partition” and confirm that you want to perform the action.

Select “Advanced”, then “Wipe Dalvik cache” and confirm that you want to perform the action.

With your phone data completely wiped, you may now install the MIUI 4 ROM. From the recovery menu, select “Install zip from SD card”.

Select “Choose zip from SD card” and choose the ROM file that you have copied to your tablet earlier.

Confirm the installation by choosing “Yes”. The ROM will be flashed after confirmation.

Reboot your device.

Congratulations! You now have Ice Cream Sandwich (via MIUI 4 Alpha) on your Galaxy Tab P1000.

but at point 8 or 9, (i don't remember, but i think it isn't too much important) i had to stop, because i stucked. so i reboot the device, and i've formatted it. the device worked like always, and so i decided to download rom manager from the market. when i launched the application i saw that i could flash the system that i had put in the device directly from there. so i touched that option and i followed the first instructions. i flash the system as the rom mangaer app told me. but when the device reboot for installing, and doing it's thing (i'm not a computer and technology expert to D: ) it stopped at the first screen, ( the one that says "galaxy tab, samsung"), and it didn't go ahead. so i reboot in recovery mode switching off the device and rebooting it pulling the volume up button + the power button, but it doesn't worked. so i tried to reboot it pulling volum down button + power button and appeared a yellow triangle with the android man and the written: downloading do not turn off target

but it stucked there like the first screen. i waited that the device discharged, and i charged it another time, but when i charge it, it appear on the screen the battery icon, but it is blocked. and now i can't open it, and it doesn't work or answer at all.

i know that it's possible that i made mistakes following the instructions, or the instructions doesn't worked.... but now, how can i reboot or format my device.

i only need to reuse, the information or the documents in it are not important.

if you can, help me, thanks :)