Adding OpenWrt support for Zyxel EX5601-T0

Hi guys,
can anybody help me getting openwrt on this router? Apparently I have the same device ( Zyxel EX5601-T1 / t-mobile branding) as of YummyHamster, has no sfp module onboard and it behaves the same on booting, requests a password upon interrupting the boot process.