That temporary fix doesn't work well. It's still impossible to make changes in menu assignment, etc...
This is something that works for me. I resized miniadspot to 20 ads and everything work like a charm!
If 20 isn't enough, just replicate module (or try with different numbers).
Here's the link for two files you need to overwrite (if you don't know how to make them by yourself).

Ok, I've added the 20 ads Mini Ad Spot for Joomla 1.5.x in downloads section, and a new article in documentation with credits to you for finding this.

Im having the same Issue with RC2 and havent found a fix here ?

Admin - Is this something you are working on or is it still the "back" fix ? becouse I cant get that to work

Im running php5

This issue has been solved (at least I thought so). Please give me all the details of your site: template, components installed, modules, server, to see if I'm able to replicate this, because this behavior never happened to me. I realize that this is happening only for a few users and I have to discover why.

The same problem ocurred with me. After instalation no changes can be made and saved. I´m having this 20 adds -component, and i reduced in less than 10. The version of Joomla is 1.5.14 with php5 in newest stable apache server application and mySQL 5.1 -version. I have quite some extensions, so I don't subscribe all these right now. I wish there was a solution for the problem... its annoying:P

Exactly the same issue, jumping right to the control panel without saving changes. I am using Joomla Version 1.5.14