FINAL EDIT! as my earlier edits below suggest, it all works if I run the program as Administrator to start with!
But I'm leaving this post here in case anyone else gets the same issue.
....
I have SampleTank 4 registered, and have used the Editor for the first time to create an instrument. All went went well until I tried Export Instrument to SampleTalk. Hilariously (and highly irritatingly), the youtube tutorial says "this is the easy part"!! Er, nope...
What happens is a window appears saying "Saving instrument", and it just hangs at 0%. The Cancel button doesn't work, and Editor has to be closed.
When I open Editor again I get the message "10 days grace period has expired". When I click OK for the Authorization Manager, I can enter the serial for SampleTank 4, which says OK.
But this makes no difference. The Editor is still (apparently) not authorized and I have no separate serial number for it. Clicking Cancel just takes me round the same loop (Load my saved instrument, Export to SampleTank ... saving 0% forever....)
I've tried uninstalling and re-installing, no luck.
So it's impossible to actually export the instrument to actually use it. Unless anyone knows any workaround? Is there something I'm missing here?
EDIT: just discovered a couple of other things which might clarify the problem:
1. When I open the existing instrument and click Save Instrument, there's an error message: "Instrument ST4 error. Cannot open file at path C:\Program Files\IK Multimedia\SampleTank Editor\Instruments" (that's where the file is). Clicking "Save Instrument as" directs me elsewhere (to my own User folder). That was where I had to save the file to begin with - I got a message saying I didn't have permission to save it in the correct folder, and to contact my Administrator! So I saved it where it told me, and copied it across later (then I just got the administrator warning to continue).
2. If I click "Export Instrument to SampleTank" and check the two boxes to "Remove skipped Round Robins and unassigned Waveforms" (either one or both), then the saving process quickly to 50% ... and hangs there instead.