It was brought to my attention today by another user at the NFPS homesite that Portal 2, and Portal 3 are now MAG 256 compliant as they have been updated to Stalker Middleware 5.0.1.

NFPS Portal 2

Code:
2.iptvprivateserver.tv = http://portal2.iptvprivateserver.tv/stalker_portal/c/version.js
= var ver = '5.0.1'; (Stalker Middleware 5.0.1)

NFPS Portal 3

Code:
3.iptvprivateserver.tv = http://portal3.iptvprivateserver.tv/stalker_portal/c/version.js
= var ver = '5.0.1'; (Stalker Middleware 5.0.1)

It was then confirmed by NFPS not long ago after my post at the homesite to another user after I checked all 5 portals.

NFPS NFPS is offline
Administrator

As the game said, portal 2 and 3 are running the latest stalker version and support MAG256. The other portals will be updated soon too.
Not sure how long the process will take for Portals 1,4 and 5 to be updated but it will happen soonish.