Estimate Fees Widget Changed to Revenue Calculator - Where's The Digital Tax?

When listing via the inventory interface (rather than upload) the Estimated Fees widget has sat there for as long as we can remember and has been a useful idiot check for fees and more recently the digitial tax Amazon have passed on, when lisitng items individually - as we do for used inventory.
So far so quick and easy.

The widget is being retired in favour of the revenue calculator - which sometimes pop-ups to the right (it doesn’t always load, so it’s up to Amazon’s usual tech standards).

So with the widget I now seem to have to enter the default postage charged each time, as this isn’t stored (as it previously was).
I cannot see the tax charged (not the VAT we can see a field for that) I’m referring to the digital tax. There are taxes on fees which are displayed as zero right a the very bottom.
I cannnot redact/set at zero the other costs section - by this I mean zero can be entered, but ‘other’ always creates a figure out of thin air which is then auto-deducted.

Any ideas?

I can see the point of it - coz it tells me just how much you poor FBA people pay for every element, but as we’re FBM only, the very swift easy functionality of the previous incarnation has been lost, in favour of this more opaque and complex arrangement.