Meghalaya GST amendments: UIN recognition, limits on retrospective registration changes, revised refund formula, and updated registration/refund forms. The amendments deem the Central GST Unique Identity Number to be granted under Meghalaya GST, restrict retrospective amendment of registration particulars absent Commissioner order, and revise refund provisions for zero-rated supplies by prescribing a formula (Refund = (Turnover of zero-rated goods + Turnover of zero-rated services) x Net ITC / Adjusted Total Turnover) with defined terms and special sub-rules for supplies under specified export notifications; quarterly refund filing in FORM GST RFD-10 with GSTR-11 is mandated and multiple registration and refund forms are substituted.