@ujang_je
It would be safest to try using your original SG/MY boot.bin combined with the fw_all.bin from US/EU x2 fw. You should then be able to safely flash back to full SG/MY. Don't forget to do HWID overrides to 1509 before you save the rgn.

If you are feeling courageous, flash the full US/EU fw with original HWID 1613 saved as OUT.rgn but be aware it may brick your Asian unit. Perhaps someone else has already tried US/EU on an Asian 50 and can advise further.