It looks like you have code in here for universal email version 3, and version 4 in the same page. I dont know if that can cause an issue.
on confirm.php lines 127 through 140 send out an email whose content is in WA_Universal_Email/WAUE_confirm_1.php using Universal email 3.0
on confirm.php lines 141 through 228 it sends out another email whose content is in webassist/email/waue_confirm_1.php using Universal email 4.0
Its in this block that the fatal error microtime_float() is occurring. microtime_float() is a function defined in webassist/email/mailformatting_php.php.
Are you sure you uploaded all your include files, especially the /webassist/ folder?