Not even sure it's actually encrypted as much as it's a memory dump, old skool .doc style.
> diabolical
You have no idea.
I've worked with devs using it (and had to debug their code more often than not): the thing is hell, through and through, from the stdlib itself (buggy as fsck[0], terribly leaky abstractions[1], ridiculously contrived[2]) to the IDE to the concepts (worse than VB, you store procedures in windows so changing the UI ever so slightly has dramatic effect on your whole codebase and since it's half static half dynamic you catch that only at runtime) to the source control (worse than VSS, and that's telling[3]) to the database (worse than your random toy-weekend-project database[4]) to the devious marketing ploys[5].
(some links in FR but you can toggle to English)
[0]: JSON parsing and generation is non-conformant, e.g translates null to empty strings. There is basically no memory management and the thing leaks like a sieve. This one can only do GET and POST "automatically", adds a topmost "Accept: * ", and actually only sends credentials on non-HTTPS: on HTTPS they're outright dropped because of a bug, so you have to implement HTTP basic yourself with the hack below! https://doc.pcsoft.fr/fr-FR/?3043007&name=HTTPRequete
[1]: Same proc as above, the overall thing and additional header field is actually a string concat, so if you want multiple ones you pass a string with those separated by \r\n, but god forbid you omit the last CRLF as the headers and body won't have the required CRLF and be right next to each other.
[2]: dict-like stuff (mem leaks included): https://doc.pcsoft.fr/fr-FR/?1514057&name=Tableaux_dynamique...
[3]: http://www.highprogrammer.com/alan/windev/sourcesafe.html
[4]: For network access they actually recommended you share a database via SMB shares before they had a "server mode", and still do for "small loads". The indexes get borked once in a while for random reasons so you have to rebuild them regularly. Their main API is something resembling low-level ISAM but with shared global state, and while they introduced a SQL implementation atop of that, it's downright terrible, severely lacking, and has zero query optimisation plan, throw in a HAVING and you can lock a 10000 records table for minutes.
[5]: Car seller tactics like "Buy a license, get a top of the line iphone/ipad for 1€", goodies strategy dialled to 11, heavily sexualised material (down to the IDE splash screen), with scantily clothed women in luscious poses, high heels, leather, you name it, full of bullet-point buzzwords, actual tagline is "develop 10 times faster" and literally "1000+ new features" for each version, dev conventions are cult-like, Stockholm syndrome is pervasive. License for a given version is lifetime (controlled by a hardware dongle labeled with legal threats) but any support is dropped the minute the next release is out (which is every year). Not that it matters, as bugs stay largely unfixed. Wikipedia page is heavily edited by their marketing team (from their own IPs to boot), forums are heavily moderated against any critical post, who get censored, to the point that one of the devs I mentioned was threatened (on the phone, they called him) of legal action for libel because he publicly reported and discussed a bug.
It's so bad that to fix bugs I implemented drop-in replacements for part of that stdlib and software code in C# (they have a .Net bridge which, quite surprisingly, works well, even dynamically generating WinDev proxy stubs from the C# classes) in well under half a day of work (which also had the benefit of moving some things to git and have actual unit testing), and had plans to port wlanguage to the CLR to help people get out of this hole. Guess what, the plan was rejected (even for bug fixing) because of purely irrational cultish reasons and I had to put intricate workarounds in my Ruby code to massage my way out of the endless brokenness, costing me overall months of work and terrible customer impact.
If it feels like I was on some sort of mission, then it's partly true, as the people I worked with were really nice folks I had real bonds with, and witnessing the brainwashing they were victim of, destroying the very real potential they had, was truly disheartening.