> It's just that
> it has to be a client server version.

Using an Thumb-Drive and doing real Client/Server seems to be an
logical contradiction: Either you intend to provide an
multi-User-Application which should not really be removable by an
single unser or you have an single user application on an removable drive.

One great advantage of Firebird is that embedded an C/S are
compatible: Just exchange the fbclient.DLL and modyfo your connection
string to switch between both versions.

Elmar