Dear Adam,
Thank you for your patience.  You last responded to my post on 1/28/13 and I've finally taken a closer look at the problem.   I originally had an issue more similar to Lucas's where I got a message after logging in.  That quickly went away, but this problem remains. 
It is happening on two accounts that I have sent you in an email.  I've clicked the Active box for Method Support for both accounts: We get the following message on the New Opportunity(2) screen when clicking on the Clear/New, Delete and Save & New buttons:
"An unexpected error occurred while processing the results in your browser. If this issue persists please contact your method administrator."
It doesn't happen on the original New Opportunity screen.  I created a new Clear button and added only the Clear Screen action, but it still happened.  It happens in both Firefox and Google Chrome.  I cleared the cache in Firefox and it didn't change anything.
Any insight you have would be greatly appreciated.
April Hooper