The post above yours is the ROM created by third party, not the ROM released by manufacturer. The instructions of use are already given in the link. You did not read ?

Or you are referring to other ROMs ?

Hi... Excuse the delay... ROM updating method will depend on the currently installed FW on the device. If it's one that supports OTA, then by all means, go through that as it's the easiest method to follow for beginners (Copy files to SD card, boot up system and choose "Update" app..) Plus the method will endeavor to retain the bulk of your settings and all already installed apps + their data. However, for a cleaner FW update? Say you want to get rid of past bugs and or just want a clean slate with the new ROM? Then, flash it using the USB method (requires flash tool and a Windows PC (typically)...Power of the box, load up FW in flashing tool, hit Start and plug in power & USB to the box..Tool should begin flashing..Wait till 100% success message is flashed.. You can unplug all and reboot into the flashed ROM). This method (done right) is "risk-free" too and should completely erase the previous ROM with the one being flashed (Yup, most times, you can safely flash older FWs), etc and install as new. You'll have to re-setup your box and install apps etc... So you decide which is for you..

It would help if you would state what device and if you've tried the usual troubleshooting (uninstall, reboot.. reinstall)...Test login on smartphone, etc to confirm it works..

if u can't log in and use new apk but still can use old one, it means you have not been migrated to new.

do u not get the message when u try to log in "your account has not been migrated..."?

the migration is in stages, slow; new subscribers get new STB, some white box user already migrated, new apk also in use.

others, very old boxes.... not yet.

unifi has been crap with communication... people get confused....