well, I clicked the links in the OP, to avoid testing something that was already tested. for your convenience, I'll sort my findings by how well they work (I spent this afternoon testing flash games on ruffle). most of them don't seem to be saving data. I don't know if this is on my end or ruffle's (some of them seem to keep my data if I reload the page, but I lose my saves if I close the tab and open it again)
anyway, I hope this helps:
Seem to be as good as they were back in the flash days:
Bloons Tower Defense 2 (https://www.newgrounds.com/portal/view/405975/format/flash?emulate=flash)
the only tower I didn't test was super monkey because I'm just bad at this game.
Bloons Tower Defense (https://www.newgrounds.com/portal/view/395153/format/flash?emulate=flash)
I was out of lives before I could test the ice and bomb towers.
Caravaneer (https://www.newgrounds.com/portal/view/381821/format/flash?emulate=flash)
More Bloons (https://www.newgrounds.com/portal/view/374372/format/flash?emulate=flash)
Age Of Japan (https://www.newgrounds.com/portal/view/391385/format/flash?emulate=flash)
never played this one before, but if the broom is supposed to clear a piece, but not the tile underneath...
Bubble Tanks (https://www.newgrounds.com/portal/view/369800/format/flash?emulate=flash)
if you always had to spam click to shoot...
Bloons (https://www.newgrounds.com/portal/view/370620/format/flash?emulate=flash)
Bloons Player Pack 1 (https://www.newgrounds.com/portal/view/386482/format/flash?emulate=flash)
Serious visual glitches, but otherwise fully functional:
Bunny Invasion (https://www.newgrounds.com/portal/view/374337/format/flash?emulate=flash)
menu screen is almost completely black, but buttons light up and respond if you manage to locate them, crosshairs are barely visible. But you can buy upgrades and they work.
You can load and hit play, but there are game-breaking bugs:
Feudalism (https://www.newgrounds.com/portal/view/401169/format/flash?emulate=flash)
I can't equip/buy/sell equipment (if I'm doing it right), can't recruit/arrange troops. some other features seem to be working, though (combat, quests, challenge the city, scrolls).
Mardek Rpg: Chapter 1 (https://www.newgrounds.com/portal/view/382579/format/flash?emulate=flash)
the game loads, but doesn't respond to input after initial cutscene (the skip button works).
Mardek Rpg: Chapter 2 (https://www.newgrounds.com/portal/view/408513/format/flash?emulate=flash)
same problem as the 1st, but the game waits untill the 2 protagonists are done talking to stop responding.
Sonny (https://www.newgrounds.com/portal/view/417513/format/flash?emulate=flash)
wasn't this one tested before? I couldn't find test results so...
anyway, this one gave me a txt error log (should I have included it in the post?)
AS3 games that gave the AS3 warning (so others seeing this thread don't waste their time on them until AS3 is supported):
PALADIN: the Game (https://www.newgrounds.com/portal/view/416507/format/flash?emulate=flash)
Anika's Odyssey (https://www.newgrounds.com/portal/view/411623/format/flash?emulate=flash)
shows a yarn ball
Sandbox (https://www.newgrounds.com/portal/view/342901/format/flash?emulate=flash)
Monsters' Den (https://www.newgrounds.com/portal/view/415012/format/flash?emulate=flash)
Bloons Tower Defense 3 (https://www.newgrounds.com/portal/view/463445/format/flash?emulate=flash)
DON'T TRY THIS ONE IF YOU HAVE SEIZURES!