Tether only works once...Waiting months for a solution

I first raised this issue in March. It is still an issue with no resolution or comment from tech support months later.

Here's the deal:

Configuration:
Mac OS 10.6.6
Tether is current (1.4.4.6 on BB and 1.1.0.2 on Mac)
Blackberry Curve 8530 running 5.0.0.654
Paired using Bluetooth
WiFi inactive on the BB

--1--
Tether on Mac is active
Mac and Blackberry are paired
When I install Mac Tether and start it up, it finds the Blackberry and connects perfectly.
It “detects the network adapter” and creates a pseudo-ethernet connection.
It works perfectly. I can browse, VPN, email, etc.
Speed is decent.

--2--
I exit Tether from the Mac application.
BB Tether reports status as: “Waiting for Bluetooth connection.”
I open Tether on Mac and connect again as normal, selecting my BB via Bluetooth.
Again, everything is perfect.
I exit from Mac Tether
BB Tether reports status as: “Waiting for Bluetooth connection.”

Now the problem:
--3--
I switch locations to another network configuration that I use with my home WiFi.
I connect as normal, everything works.
I disconnect and return to the location/configuration that has my Tether setup
I launch Mac Tether
I connect to BB
BB Tether reports “Connected to PC via Bluetooth”
Mac Tether reports connection active with 0 packets or data transferred
I launch my browser and nothing works.
In the Network Preferences, the Tether service (with Ethernet icon) shows as not connected with the status reporting as “cable unplugged.”
I can’t get service through Tether

If I delete and reinstall, everything works again until I switch network locations or interfaces.
What’s the deal?
I can’t really reinstall every time I use the app.

Ok, I've tried to reply to the question below and I've contacted Mark directly with no response. Let me answer the question here and see if anyone has an idea.

I haven't tested USB and don't want to disable and uninstall RIM BB Desktop. The BT application works fine on the first, clean install.
BT does show as connected on both BB and Mac