Hi Alex, it's possible to replicate a single object along a path using the Transform > Array > Curve command, but there is not currently any way to sort of morph an existing arrangement of objects along a path like you want to do there.

For that the easiest way currently is to do text along a curve in a 2D illustration program and then import that by AI format into MoI and extrude it.

You can get Creature House Expression from here which is able to do the 2D creation part:
http://download.microsoft.com/download/a/5/d/a5d625a5-2e3d-4e9c-8608-6de48d7b569f/CreatureHouseExpression3_3.exe

I do expect to be working on some new kinds of morphing type tools in MoI v3.

- Michael