I had the same problem and found out that the system either the WYSIWYG or the component was adding in br tags after each line of code for a table. I ended up having to eliminate all whitespace in the code for the table so that it's all one chunk.
We are experiencing the same problem. This is very frustrating.
Our installed version of DT Register is 2.7.6a. We are using JCE editor version 1.5.7.12.
I cannot see any br tags in the HTML code. Would appreciate some help with resolving this. A simple task of editing a thank you e-mail has become a nightmare.