I'm glad that the work around did the trick for you, this confirms for me what the issue is. Here is what I did on your page to get it working.
On renew_confirm.php on line 216 you have the $WA_columnTypesStr variable. This is where the change needs to be made. What I did was match up the column you were having a problem with in the $WA_fieldNamesStr variable. The OrderDate was the fourth value in the list so in the $WA_columnTypesStr I adjusted the fourth value. I changed it from ',none,'' to this none,none,NULL, here are the before and after versions of this variable:
before
$WA_columnTypesStr = "none,none,NULL|',none,''|',none,''|none,none,NULL|none,none,NULL|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|none,none,NULL|none,none,NULL|',none,''";
after
$WA_columnTypesStr = "none,none,NULL|',none,''|',none,''|',none,'|none,none,NULL|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|',none,''|none,none,NULL|none,none,NULL|',none,''";
I will ensure that a proper bug is logged for this issue. If you have any trouble making these updates yourself post back with the code for the server behaviors that are on these pages and I will help you out with that.