I was about to delete the post, but thought I'd keep it in case anyone else may be looking for a similar solution.
Turns out that I was over-complicating the breakdown of the multi-select fields. (used that break down method to design bulleted <li> points under a different scenario.
The solution here is simply to refer to the actual multi-select field itself in the API_AddRecord call, and it works like a charm.
So the working code for this would be something like this:
var text SIGNIN = URLRoot() & "db/main?a=SignIn";
var text APPROVED = URLRoot() & "db/" & Dbid() &
"?a=API_AddRecord&_fid_6=" & [First Name] &
"&_fid_7=" & [Last Name] &
"&_fid_61=" & [Related Company Enrollment Form]&
"&_fid_70=" & [Product ERP] & // Multi-select field
"&_fid_71=" & [Product Add-On Apps] & // Multi-select field
"&_fid_72=" & [Product Accessory Apps] & // Multi-select field
"&_fid_73=" & [Platform] &
"&_fid_9=" & [Email Address] &
"&_fid_10=" & [Office Phone] &
"&apptoken=xxxxxx" &
"&rdr=" & URLEncode(URLRoot() & "db/" & Dbid() & "?a=dbpage&pageID=10)";
"<a class='Vibrant Success' href='" & $SIGNIN & "&NextURL=" & URLEncode($APPROVED) & "'>APPROVED</a>"​
Cheers!
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George Khairallah
CTO
gotomyerp, LLC
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