Hong Kong and Macau travel

I am an Indian, live in HK and hold HKID. I am not a PR yet. My mum (indian citizen) will come to HK for total three weeks. I am trying to get a long term tourist visa done. During the stay, after 16 days of her arrival (Can't do it earlier) I plan to take her to Macau for two days, one night and then again return to HK and stay here for another 5 days before flying back to India.
I am applying for multi entry permit, but in case immigration grants a single entry only - will this trip to Macau cause any issue in re-entering HK? Anything specific I should mention in the form? I am also filling up a sponsorship form while applying for her entry permit.