So far I've found:
IM2
- Broken out to two tables now
- IM_ItemWarehouse
- IM_ItemWhseHistoryByPeriod
IM3
- There used to be two fields for ReceiptDate, ReceiptNumber (ReceiptDate2, ReceiptNumber2) - that seemed to vary based on the type of record being received. I'm assuming that Sage changed this and now the conversions fail because the '2' have been normalized so that there's no longer a need for 2 fields.
IM9
- This used to hold period 1 - 13 sales, quantities, COGS
- Now holds period by period