It is best to create a GEDCOM from RootsMagic with the option " Extra Details (RootsMagic Specific)" unchecked.
WorldConnect does not properly handle user defined GEDCOM tags. You need to tell World Connect which GEDCOM tags to ignore.
In Rootsweb WorldConnect, when you "Edit Your Family Tree", login using the advanced setup. Go down to Line 32 Option "Tags to Remove". Enter the string below of unneeded tags. Then Upload/Update your database. The unwanted tags will disappear:
_UID,_SDATE,_COLOR,_TMPLT,FIELD,VALUE [note -- there is a comma between each parameter]