hello s l,

i dont think so that there is nay issue you will be facing while mentioning your last name i.r surname in the gate pplication , as each and every infromation you need to fill out there, every personal details. as mentioning the full name is necessory so you need to mention , and if you are facing any issue, then just let me know what type of issue you are facing. so that i can help you out.  so all the very best have a great future ahead.