Hello, we did a lot of development in filemaker solutions ( I suppose we have done more than 100 solutions for firms) here in belgium (since 1995!). If you want we can help you. We are using XP systems, but some of our clients are MacOSX running. There is no problem for us to develop for both.
What you exactly want is not very clear but not a problem. Communication and cooperation can be done by using remote control systems, etc.
I suppose you are also working on filemkar so it should be nice to have a company to share knowledge and solutions.
Filemaker 8 is now our development tool.
thanks
Luk