Formulas in For Email Body Failing Mysteriously

Thanks, but that raises more questions. 
The button to invoke the email is standard:

"mailto:"&[Submitter.Email] &
"?subject="&[Email.SubjectLine: CTS_Evaluation_Completed]&
""&"&body="&[Email.Body: CTS Evaluation Completed]&""

The problematic component is body field.   I understand that this button is constructing a URL, using the computed result in the body field [Email.Body:CTS Evaluation Complete] .   

I'm not using URLEncode in the body at all.  I'm constructing a large string of defined text blocks concatenated together, using formulas to determine which blocks to select. 

Throughout, I use the &"%0D%0A" & "%0D%0A" & for paragraph returns, and it works just fine.    The problem arises when I simply add that one extra text block MyTextB.   Even if it just 14 chars of straight text, no spaces or special characters, then the entire thing fails. 

Indeed, I just ran another text and setting MyTextB to "AAAAAAAAAAAAA" worked, but "AAAAAAAAAAAAAx" failed.  That was the only change made, adding "x", and bingo. Nothing.  

I do use chars including : and / in the other texts but that does not cause any problems.  

Still stumped...

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ROBERT SACHS
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