Multi-company processing?

Is anyone using multi-company processing?
We create customers in company 20, make them global, and they get linked int our secondary company HUS. Since we went to 9.04.506C -
We're having a lot of problems.

Getting invalid customer# errors, but yet everything looks ok.

We use Alternate billto's, but the custbillto.btcustnum in 2nd company HUS still contains the same# as found in the original company.

We have it set so Shipto.TerritoryID should be manually entered on the 2nd company but it is coming thru from company 20 - which if you are using CRM and workforce - an invalid territoryID will make that shipto record unavailable to a BAQ - causing bad dashboard and report results.

Is anyone experiencing these types of problems?

Is anyone using multi-company processing and it's working well that I could discuss my setup with?

Things seemed to work ok in V.8.04.xx but in E.9.04.506C I'm having a lot of problems.