IS it enabled? If so, make sure the creator field is included within this layout. Otherwise it may not be able to set the creator.
Below is the content in Event Edit page.
{{Message:MESSAGE}}
<div class="adminform">
{{Tab Start:TABSTART#JEV_TAB_COMMON}}
<div class="row jevtitle">
<div class="span2">
{{Title Label:TITLE_LBL}}
</div>
<div class="span10">
{{Title:TITLE}}
</div>
</div>
<div {{Priority:PRIORITY# class="row jevpriority" #class="row jevpriority jev_none"}}>
<div class="span2">
{{Priority Label:PRIORITY_LBL}}
</div>
{{Priority:PRIORITY#<div class="span10">%s</div>}}
</div>
<div {{Creator:CREATOR# class="row jevcreator" #class="row jevcreator jev_none"}}>
<div class="span2">
{{Creator label:CREATOR_LBL}}
</div>
<div class="span10">
{{Creator:CREATOR}}
</div>
</div>
<div {{Calendar label:ICAL_LBL#class="row jevical" #class="row jevical jev_none"}}>
<div class="span2">
{{Calendar label:ICAL_LBL}}
</div>
<div class="span10">
{{Calendar:ICAL}}
</div>
</div>
<div {{Lock Event:LOCK#class="row jevlock" #class="row jevlock jev_none"}}>
<div class="span2">
{{Lock Event label:LOCK_LBL}}
</div>
<div class="span10">
{{Lock Event:LOCK}}
</div>
</div>
<div {{Form list of one category:CATEGORY# class="row jevcategory"#class="row jevcategory jev_none"}}>
<div class="span2">
{{Category label:CATEGORY_LBL}}
</div>
<div class="span10">
{{Form list of one category:CATEGORY}}
</div>
</div>
<div {{Access:ACCESS# class="row jevaccess" #class="row jevaccess jev_none"}} >
<div class="span2">
{{Access label:ACCESS_LBL}}
</div>
<div class="span10">
{{Access:ACCESS}}
</div>
</div>
<div {{Published State:STATE# class="row jevstate" #class="row jevstate jev_none"}} >
<div class="span2">
{{State label:STATE_LBL}}
</div>
<div class="span10">
{{State:STATE}}
</div>
</div>
<div {{Event Colour:COLOUR#class="row jevcolour" #class=" row jevcolour jev_none"}} >
<div class="span2">
{{Colour label:COLOUR_LBL}}
</div>
<div class="span10">
{{Event Colour:COLOUR}}
</div>
</div>
<div class="row jev_description" id='jeveditor' >
<div class="span2">
{{Description label
ESCRIPTION_LBL}}
</div>
<div class="span10">
{{Description
ESCRIPTION}}
</div>
</div>
<div class="row jeveditlocation" id="jeveditlocation">
<div class="span2">
{{LOCATION label:LOCN_LBL}}
</div>
<div class="span10">
{{Location:LOCN}}
</div>
</div>
<div class="row jev_contact">
<div class="span2">
{{Contact label:CONTACT_LBL}}
</div>
<div class="span10">
{{Contact:CONTACT}}
</div>
</div>
<div class="row jev_extrainfo">
<div class="span2">
{{Extra label:EXTRA_LBL}}
</div>
<div class="span10">
{{Extra:EXTRA}}
</div>
</div>
<div class="row">
<div class="span2">
Example of single custom field : {{Custom joomlauser2 label:customfield_joomlauser2_lbl}}
</div>
<div class="span10">
{{Custom joomlauser2:customfield_joomlauser2}}
</div>
</div>
{{Custom Fields:CUSTOMFIELDS}}
{{Tab Start:TABSTART#JEV_TAB_CALENDAR}}
{{Calendar tab content:CALTAB}}
{{Tab Start:TABSTART#Custom Fields Tab One}}
{{Tab 1:CUSTOM_1}}
{{Tab Start:TABSTART#Custom Fields Tab Two}}
{{Tab 2:CUSTOM_2}}
{{Tab Start:TABSTART#JEV_ATTENDANCE}}
{{Attendance Tab:JEV_ATTENDANCE}}
{{Tab Start:TABSTART#JEV_INVITATION_OPTIONS}}
{{Invitations Tab:JEV_INVITATION_OPTIONS}}
{{Tab Start:TABSTART#JEV_REMINDER_OPTIONS}}
{{Reminder Tab:JEV_REMINDER_OPTIONS}}
{{End Tabs:TABSEND}}
</div>
When I click Publish on this custom form I get
Message
You are attempting to publish a customised layout that is the same as the default layout - it has therefore NOT been published since this is not necessary and can lead to complications at a later date. You should only publish a layout if it has been customised.
I haven't donw any changes to any of the custom layouts.