When you grapple on a left wall with grapple blocks, until you get the "wall jump"-like sprite, and you let go of grapple, then a mismatch is detected (with the 300 counting down like said it the readme). I've tested this in 2 rooms that the community calls "aqueduct" and "halfie climb room".
console output:
@3549: Memory compare failed (mine != theirs, prev):
0x000AF9: A0 != 00 (A0)
0x000B13: A0 != 00 (A0)
0x000DA2: 01 != 00 (01)
0x000DA5: 00 != 60 (00)
0x000DD0: 00 != 01 (00)
total of 5 failed bytes
Verify failure!
@3550: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3551: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3552: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3553: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3554: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3555: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3556: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3557: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3558: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3559: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3560: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3561: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3562: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3563: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3564: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3565: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3566: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3567: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3568: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3569: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3570: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3571: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3572: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3573: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3574: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3575: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3576: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3577: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!
@3578: Memory compare failed (mine != theirs, prev):
0x000DD0: 00 != 01 (01)
total of 1 failed bytes
Verify failure!