This is a user to user forum, so the exception details won't say much to us.
You say you try to add a script, but you have noscript tags. Are you sure that this problem is related to those tags? It may very well be a fluke that has to do with something else.
Help > Contents & Index > Using RoboHelp 9 > Advanced program features > scripts
This is how the above is entered in a topic: (HTML view)
This is how the script/tags should appear.
The system does not freeze up every time. I can work on a few topics (maybe 5 or 6) then it will freeze. I am not sure if the problem has anything to do with inserting a script but this is the only time it freezes. I use RoboHelp on a daily basis and is in it all day long for I am a Technical Writer assigned to preparing and updating online manuals. If I am creating a new topic or updating content on a topic (Design view) the system doesn't freeze up.
I have completed one WebHelp project and have a few more to do. I am not sure if inserting the script is causing RoboHelp to freeze. It could be the constant switching between Design and HTML mode or it could be the Add-On to Microsoft Visual Studio. We use Visual Studio to store all the files for the online manuals. Additionally, I tried adding the script while in HTML view but it didn't work for some reason or another using RoboHelp HTML v9. That's what started my investigation into how I can add these lines of HTML coding. All I know is that with the hundreds of files I have to update, having RoboHelp freeze so much is presenting a problem for me. Hope this information helps.
The way I took care of this problem is by entering the script in a text file and copy/paste it into the HTML view. The system stopped crashing/freezing and I am able to continue with ease.