The ticket I created specifically asked for scripts to clean up the Dell Management Console, but all they wanted to do was remote control my computer to see the error for themselves. I sent them screenshots and haven't heard from them since.
I did a repair of the SMP and tried to edit a computer again, and this finally showed up in the log viewer:
Priority: 2
Date: 2/27/2012 9:06:09 AM
Tick Count: 118868187
Host Name: SERVERNAME
Process: w3wp (2000)
Thread ID: 15
Module: w3wp.exe
Source: Altiris.AssetContractCommon.Web.Manager.EditCreateResource.Page_Load
Description: Exception encountered: Altiris.NS.Exceptions.AeXException: An unexpected exception has occured during CreateInstance. (Assembely:Altiris.PatchManagementDell, Version=7.0.0.0, Culture=neutral, PublicKeyToken=d516cb311cfb6e4f Type:Altiris.PatchManagementDell.DataClasses.DellComputerModel) ---> System.IO.FileNotFoundException: Could not load file or assembly 'Altiris.PatchManagementDell, Version=7.0.0.0, Culture=neutral, PublicKeyToken=d516cb311cfb6e4f' or one of its dependencies. The system cannot find the file specified.
I sent another request to Support for the scripts to clean up the Dell Management Console this morning...