Altium deisgner: drawing 4x10k resistor
Here is what I use for this situation (custom part): 



There is one part designator (it's one part). I prefer to show the pin numbers. 

It's also possible to create a part with sections A, B, C, D, or to have two options for the same type of device (so you can use the most appropriate symbol for a given situation). 

To create individual sections, you create a part that looks like a single resistor in the shape of your choice. Then select the part in SCH Library and use Tools->New Part (not New Component) several times and you'll have this: 



Then select each section and edit the symbol and pins to agree with the physical part. More in this tutorial. 

The default designator for the above situation is R?A. to R?D, as you said you want, but you may prefer to alter that if you are doing multiple channel design.