I've just confirmed 78/80 on the PC version, with a screenshot available in e-mail.
Unfortunately, this is with the method that is supposed to get 79/80. A0;
The method does work! B) I finally managed to confirm 79/80 on the PC version.
A screenshot is available, though it doesn't reveal much (I was rather excited and almost forgotten to do the screenshot, so cut me some slack.) It does have enough to show that 79/80 will survive, but since I captured relatively late, it doesn't reveal at all the critical details. Screenshot can be received in e-mail (guestlevels at the usual place). I'm also willing to give hints and the like in e-mail to those who want to try for themselves on lose 3 and beyond.
As I was watching, at one point there was almost a leak. And in fact for a moment it did leak, but fortunately the next stroke came just soon enough to unleak those 2. (I'm sorry I'm trying to be deliberately unrevealing, I guess mostly for those who don't even know "lose 10" yet.) Based on this observation, the conclusion is clear: you have to bash as close to the wall as possible. One pixel off can be enough to make the difference between lose 1 and lose 3.
So this is definitely (pun intended) "tricky" no doubt, indeed I think this is probably harder to execute than the 100% on Mary Poppin's Land.
--------------------
So as an update, the ultimate challenge has now gotten down to losing a total of 69 lemmings.