Questions on ADC and tivaware with TM4C1230E6PM

Hi all, I am having a few issues with the ADC in an existing project (initial code works great but am having issues with adding another ADC input).  I am inclined to work a bit more on the issue on my own before posting code here.  But I do have a few questions on the ADC that I haven't had clarified in the reading and searching I've done.

1.  Is it necessary to have an ISR for the ADC if I am only using the ADC interrupt in the while statement in the adc read function?

while(!ADCIntStatus(ADC0_BASE, 3, false))    {  }

It has worked fine before adding my second ADC input.

2.  Can the ADC inputs set up with ADCSequenceStepConfigure be out of order, i.e.

ADCSequenceStepConfigure(ADC0_BASE, 3, 0, ADC_CTL_CH0);

ADCSequenceStepConfigure(ADC0_BASE, 3, 1, ADC_CTL_CH2);

ADCSequenceStepConfigure(ADC0_BASE, 3, 2, ADC_CTL_CH1 | ADC_CTL_IE | ADC_CTL_END);

3.  Does single use ADC input pins (such as PE3/AIN0 pin 6 on the TM4C1230E6PM) have to be declared with a GPIOPinTypeADC in setup?

4.  Can the ADC input pins be configured with GPIOPinTypeADC prior to executing SysCtlPeripheralEnable for the ADC?

Thanks for the help, if I continue to stay stuck I will start another thread.