inter company transactions with Navision 3.70A

Can anyone share their experiences of using the advanced multi company add on from To Increase with Navision 3.70? We want to have two business units - separate legal entities - set up as separate companies. One needs to sell inventory to external customers, invoice them however the actual inventory is shipped from the second company. The first one gets the revenue. So we need to use inter company transactions. I would like to know if anyone has done anything similar on Navision 3.70, have they used the To Increase pack to facilitate it, (or some other add on), and what their experiences are?

Why not upgrade to 4.0 where this feature is already standard ?

Thomas Navision 3.70A is already live with various other customisations for one business unit, which would require lots of regression testing, so we are not able to upgrade to v4.0 within the timescales of our current project.

Have you looked at 4.00 and identified the inter-company functionality? Can you isolate that finctionality and migrate it to 3.70? This could save a lot of time.

Can’t you talk to the company that developed th eAdd-On? They should ave a 4.00 ersion, and at the least will be able to tell you if they can give you advanced 400 features in your 370 AddOn.