public static void SendEmail(emailParam[] emailParams)

What is this expecting? List? 

<lightning:combobox aura:id="selectItem" name="status" label="Status" placeholder="Choose Status value="new" onchange="{!c.handleOptionSelected}" options="{!v.statusOptions}" readonly="false"/>

The documentation also says the the combobox will default to readonly="false" but it seems to default to true, and input into the component is not possible.

public static void SendEmail(emailParam[] emailParams)

What is this expecting? List? 

I wrote this code, but every now and again I get the Too many DML statements error. I am thinking if I just have it batch at 150 a pop, I should be good, but none of my attempts seem to work. Any suggestions would be appreciated.

trigger NewOwnerWelcome on BXG_Contract__c (after update) {
    for (BXG_Contract__c acc :Trigger.new) {
    if(acc.timedelay__c == True){
        Case welcomecall                  = new Case();
        welcomecall.Description           = 'Give Owner Welcome Call';
        welcomecall.Routing__c            = 'Welcome Call';
        welcomecall.Area_Responsible__c   = 'Customer Care';
        welcomecall.Department__c         = 'UNO';
        welcomecall.Origin                = 'BXG Contracts';
        welcomecall.Contract_Number__c    = acc.BG_Contract_Number__c;
        welcomecall.BXGContracts__c = acc.id;
        insert welcomecall;
        }
}
}