Upgrading Drupal

Hi! I've installed drupal 4.7-beta-6 and been customizing some files, mostly node.module, to add some xsl stylesheet support for the rss feed, and a few minor changes my site required and were not in the released version.

What would u recommend? Should I upgrade to 4.6 first?

hey dudes,

drupal is blowing my mind, it is sooo cool...

however... i have one problem...

i'm using drupal for my band's website... and we needed a great tool for uploading and playing songs...

we thought we found the greatest tool ever made, ever...

until we realized we had to upgrade to drupal 4.7 RC2.

through reading these forums i realized i made some basic mistakes on the upgrade process...

like turning off the modules i added in order to do the upgrade... etc etc...

Updating from 4.6.6
Backed up database
Removed everything from server except existing database
Uploaded 4.7 RC2
Ran update.php with the following results............

Error message:
An HTTP error 12152 occured. update.php?op=do_update

Log messages:
The update process was aborted prematurely while running update #147 in system.module. All other errors have been logged. You may need to check the watchdog database table manually.

Now left with nothing for my Drupal install except a "Page Not Found" error message.

This error message was spit out after an upgrade from 4.7 beta to 4.7 RC2, it only occured on one of my Drupal instalations and only on one page node.
User warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'OR format = 1' at line 1 query: SELECT * FROM filter_formats WHERE OR format = 1 in /home/ariadoss/includes/database.mysql.inc on line 108.

I've never upgraded drupal and didn't find a readme in the drupal install to figure out how to upgrade drupal. Can someone tell me the steps, or if there is a file, what file it is.