As Eollie mentioned it would be best to install the ROM and gapps from the recovery as ROM Manager will only wipe 2things instead of 3,and doesn't format the 4 that need to be formatted. The residual data from not wiping thoroughly enough will corrupt the new ROM.
This is very simple and easy to do.
If you used the Gingerbreak.apk did you install Busybox(download a Busybox installer from the market)?
Did you install the proper flash_image?
I'm assuming you did,but don't know for sure.
Here is everything you will need to get a proper install of a IHO-CM7 ROM:
1. You will actually need two recovery's. Xionia_cwma_12518.4,which is good to have on the sd card because it has an option in the advanced section that will fix a recovery loop, which can be found here
http://www.mediafire.com/?fbaoutnaw717pnb . And what ever CWMod recovery you decide to flash to the phone. With the new IHO-CM7 gingerbread ROM's the recomemeded recovery is the asopCWMod version which can be found here
http://www.mediafire.com/download/w7i63039n8a7zb2/aospCWMod-VM670-20110531.img
2. The flash_image can be found here
http://www.mediafire.com/?bx14hzq5i2pq3ps
3. The IHO-CM7 ROM of your choice. I like the BACKside ROM which can be found here
http://www.mediafire.com/?k9f3upodohiwiwo . This will also require the gapps(google apps) which can be found here
http://wiki.cyanogenmod.com/index.php?title=Latest_Version/Google_Apps Make sure you use 20110613 signed.zip. These can also be found at the Devs site here
http://androidforums.com/optimus-v-...wip-backside-rom-cm7-green-machine-theme.html .
4. Make sure you unzip the recovery and the flash image when you put it on the Root of the sd card(put them somewhere near the bottom of the list of file folders on the sd card). The ROM and Gapps need to stay zipped and be put on the root of sd card as well.
5. using a file manager like ES file explorer rename the CWMod recovery image to recovery.img
6. Open the terminal emulator and type in:
su(return)
mount(SP)-o(SP)remount,rw(SP)-t(SP)yaffs2(SP)/system(SP)/system(return)
cat(SP)/sdcard/flash_image(SP)>(SP)/system/bin/flash_image(return)
chmod(SP)755(SP)/system/bin/flash_image(return)
flash_image(SP)recovery(SP)/sdcard/recovery.img(return)
reboot(SP)recovery(return)
(SP)=This is were a space should be,do not actually type in (SP)
(return)=do not type this. Just hit the enter key(the one on the bottom right)
6. You should now be in your recovery. To scroll use the up/down volume keys. To select use the camera key. This first thing(and most important) you need to do is go to the backup and restore section and select backup(this will make a backup of your current system in case you make a mistake with the ROM install).
7. Now you need to do all these things(this must be done when installing a new ROM or restoring a backup).
1.wipe cache partition.
2.wipe dalvik cache(advanced section)
3.wipe data/factory reset.Now that your rooted YOU MUST NEVER USE THE FACTORY RESET IN THE PRIVACY MENU ON THE PHONE
4.format boot,system,data,and cache
5.go to install zip from sd card
6.go to select zip from sd card,chose the ROM first. It will go thru the install procedure. When done go back to step 6. and select the gapps.
When all this is done select reboot system now.
It will take 5-10min. for the initial reboot. You will be asked to sign in,skip this.
Now you can go to the market app and click on it and sign in to your google account(you must have your e-mail address and log in code).Reboot the phone twice then set up your apps. Once you get everything set up just the way you like it and all your apps are just where you want them,go back into your recovery and make a backup of that ROM. You can now delete the first backup if you need to (you might keep it if you ever need to revert back to stock to sell the phone).
If you want to install a theme all you have to do is go into the recovery and wipe cache partition and dalvik cache,then do the same thing you did to install the ROM(theme must remain zipped)
When you need to install an update to an installed ROM,all you have to do is wipe cache,and dalvik.
To change the boot animation (must remain zipped) go to /system/media(make sure that you have changed permission of the system from r/o to r/w) and delete the boot animation found there. Then copy the boot animation you have on the sd card and paste it where the old animation used to be(on next reboot it will be there)