How to contact NAS from outside of my network?

[Mikeyy 49]

Setup:

I have Asus N66U with latest Merlin FW. VPN client is setup to connect to AirVPN. Redirect internet traffic is set to "Policy rules" which say to route only 1 LAN device (192.168.1.11 which is my Synology NAS) through VPN.

This is all working fine.

 

Problem:

I want to connect to my NAS (from work, or hotel etc.) over regular internet, not through VPN. Since NAS is set to go through VPN, it just refuses connections originating from regular WAN. Is there a solution for this?

 

P.S. I don't want to port forward through VPN. I would need a lot more lines of text to explain why, so lets mark that as not acceptable solution.