I've been upgrading a site from 1.3.9 to 1.5.1.

I believe I have everything working correctly but still need to configure the payments module. Using the existing, live site's admin v1.3.9, I have transferred the api login id, transaction key and matched the settings using radio buttons.

I have 2 issues:

(1) a warning "Authorize.net (AIM) (in Testing mode) (NOTE: MD5 Hash key too long)"

and

(2) in edit mode the module displays 3 textfields with no labels or information about what belongs in each one. (the live store v1.3.9 gives no help in trying to figure this out)

So, is the transaction key (36 characters) the same as the MD5 Hash key that's too long? And how do I figure out why the 3rd, 5th and 6th textfields offer no guidance?

Any suggestions on finding a solution?