I recently upgraded (late) to 3.02.135 due to an issue I was having. Turns out my problem was hardware related, nothing to do specifically with BT.
Since the upgrade I have noticed some odd behavior with the tax calculations as well. I haven't been able to pin down a pattern since some sales to Canadians are having taxes applied correctly and some are not.
I'm not clear why this is happening, I'm under the impression that the tax calculations are totally independent of any settings on eBay but perhaps I'm wrong.
I was going to wait a bit longer before submitting a report to BT support but I'll send one in for Monday morning.
Can't comment on the combined shipping issue as I don't use that function.
For the moment I'm just monitoring the sales closely and manually calculating the taxes where required.

"What else could I do? I had no trade so I became a peddler" - Lazarus Greenberg 1915
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