Hi there
Thank you for your responses & suggestions.
I need to make it clear I know something about backing-up Windows and do so now & then on external drives.
Back-ups have saved me in some critical situations like when some botched installation of Kaspersky for some unknown reason, that even Kaspersky support could not identify led to a total strike of the keyboard, even in safe mode. No way to even use restoration point, etc
In the process of trying to retrieve data by connecting the drive to another PC via an adapter, something went wrong that killed the HDD. A back-up saved me after having to buy a new HDD, though I lost data that was not updated to back-up external HDD.
There are less dramatic situations however when one needs to make a fresh installation because of some issues. I'm a regular visitor to Microsoft Answers and know there are lots of problems whose only solution is a fresh installation recommended by support, because everything else fails. Also once in a while, one just needs some clean Windows, which runs faster.
Also depending on one's situation, if you are for some reason always installing & uninstalling a large number of programs & gadgets, which are not always perfect, sometimes one needs fresh Windows because of their effects.
My laptop was originally Windows 8 based. I upgraded it to Windows 10. That for example made all back-ups of Win 8 useless. Just trying to say there are situations and believe me lots you may have not thought about where your suggested solutions (VM, Cameo) may not help. I have Virtual Box, but it's not practical or always appropriate in my case to use to for most video/graphic programs, which involve lots of multitasking.
Sometimes users lose their license because they try to update, either by free will, or because they did not uncheck the automatic update feature. In that case the original registered Cameyo can be re-activated. provided you kept a backup of the original Cameyo. I use 7z to make those backups and store them in my 1 TB DropBox.
Having profited from GOTD for years now, I'm quite aware of that possible problem of automatic updates and it's certainly not an issue for me. I may have last had such a problem 3 years ago.
In the section "For Developers", GOTD writes "We guarantee, that the offer will be available for the limited time only, agreed by our company and software publisher, and the registration offer will expire once this agreed period is over."
The developers offer the software in the hopes that people who find it useful will buy it. They don't have any incentive to alter the GOTD license terms to allow future re-installations. Note, however, that several developers do allow re-installation by downloading from the "member" area of their websites using your registration info.
You are right and I appreciate those facts.
That's why I mentioned that there are other existing Giveaway sites I will not mention, since I'm not sure it's appropriate, where a slightly different model seems to be used. Most downloads are actually offered for more than a day. You provide an email to which they send a download link and key or you get both on the respective site.
The most important thing is downloading the program in time. Most can always be installed & activated even after the Giveaway day as long as you have the license key, which they provide.
I never have a problem after a clean installation of Windows re-installing them, except those mostly from GOTD that required immediate activation.
These sites do not seem to lack developers offering software. One almost always has more than one Giveaway per day.
As said, lots of software they offer, soon or later turns up at GOTD or before, including stuff from Reallusion (Crazytalk, etc), iObit, Cyberlink, Ashampoo, SoftOrbits, Auslogics, ... lots of pdf/document converters, diverse audio/video converters, etc. I'm aware Cyberlink & Ashampoo require extra registration on their sites where you download files from, etc. It's just that they are the ones I can quickly think of that are often offered there and at GOTD.
By the way whereas some Giveaways have licenses for 6 months (like iObit, mostly), some a year, on the specific sites I am referring it, somehow, a good fraction DO NOT.
I was merely suggesting may be GOTD could consider negotiating a different arrangement with developers that allows activation not being tied to the day of the Giveaway, at least not for all or almost all programs offered there. I'm not talking about length of license. It's fine if they want to offer 6 months or a year or unlimited. Just make it possible to activate, for as long as the license is valid, beginning from the Giveaway day.
If I did not know these specific 3 or so sites, I would not be aware a different arrangement was possible as I came to know about GOTD long before them.
If the arrangement at GOTD is for some reason cast in stone and cannot be changed, ever, that's OK. ;)
Regards