Mikrotik SXT Lite 5 not sysupgrade image on master branch

Hello everybody. I have a Mikrotik SXT Lite 5, i see that in the last months the sysupgrade image for this devices not exist anymore in OpenWrt Download Servers. A try many times build my owner firmware image, but when i flash the device enter in bootloop.

What's is the status at this moment with this devices?

Best regards, David.