Ah, yes! Unlike other scriptable apps Tinderbox expects a new app name when the version changes.
To keep scripts from breaking when the version number changes one could use …
tell application id "Cere"
instead of …
tell application "Tinderbox 9"
Why “Cere”? Only our designer knows for sure. 
You can get the id for any application with something like this:
get file creator of (info for (path to application "Tinderbox 9"))