Silent Preset
I have heard back from UVI, but the good news at my end is that with a fresh update on the UVI portal, I can now play the formerly silent Many Things (from the Falcon Library, Meditative sub folder). It works again, and it is good to have it back. It sounds very nice, but I have to admit I like it most for its name!
Channel Robot's Ambicon
Since the new update today, I can now play every one of these presets with their samples. However, it doesn't happen automatically. For a number of them - including the first on the list, Abasement (which is where I would keep a boiler). I believe a number I had trouble with are now working fine, but some, like Abasement, require an extra step to load and an extra step after that to fix.
First, double click on the Part's (patche's/preset's) name as usual. Then up will pop a message saying
'Couldn't load the file 'E:/UVI .... etc.' two files in the case of Ambicon.
You are presented with two options:
'Find all missing samples' and 'Discard all errors'. That's right, you take the one on the left.
'Find all missing samples' takes you to a page where you can navigate to anywhere on any of your hard drives. But just click on Ambicon. You likely have it saved under places; otherwise navigate to it via Devices.
Double click on 'Samples'. Nothing will appear to happen.
Then click 'OK' in the bottom right. Don't click 'Close' or nothing will happen.
Hey Presto, the angry tortoise-hating-rabbit, the magic is done! You're samples are loaded and you can play and/or edit the patch.
Now, if you do nothing more, you will have the same issue every time with these presets. To fix that, you now have to 'Save Program and Samples as...' save it to the location where you already have Ambicon. And save this over the original version.
And now it's fixed.
Yay!
Edit to add: this worked on Abasement, but not on WinterWhistpers. The latter is a multi, I don't know if that made a difference. You can still access it by finding the samples as described, but saving anything with the samples could be difficult.
I retract my 'Yay!' and offer a qualified 'Well, that's not so bad.' Edit to add: it looks like you can just 'Discard all errors' and proceed without problems. Plus, Ambicon gives you all of the samples in an accessible folder. So if you want to use them to create a patch, you can take them from there; or start you tweaking from one of the other patches that doesn't have a problem and import the samples you want there.
UVI's reply to my query
To their credit, they were very fast, replying the same day.
Regarding the silent preset, I was told that they are waiting for information from their team. That likely relates to the new update today.
Regarding the Channel Robot issue, they told me to refer to Channel Robot. Fair enough, up to a point; and I had already said that I would do that and that I was just providing them with information. Indeed, I was providing them with information about their update, which had created a problem for a third party expansion using their software. I'd have thought that that would be of considerable interest to the programmers and shareholders. But it was not of interest to the Support Team and I don't know if the information was passed on to those who could have benefitted from it.
The person who wrote to me was very friendly otherwise. So, overall, I say bravo UVI.