I checked out demos from the blitter active problems from winuae testing group and found one that causes a problem in Denise nightly 1040 (A500 ECS 1.3 512+512):
Application-Trackmo.7z ... Stops at some point in the demo! (in The Zone!)
PS. It stops on at different piont, depending on whether it is the disc inserted at WB screen or on bottom power icon!
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Party Pack 10 (Packdisk) by Artstate -->
http://janeway.exotica.org.uk/release.php?id=105525
F4 - Fortnite OCS Cractro ... some gfx problem if started from pack disk!? (same in WinUAE)
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Problem: If disk is inserted on screen bottom power icon, i.e. or after a hard reset!
Possessed-CemeteryOfSilence.7z ... Scroller glitches! (in The Zone!)
BLACK_ROBES-GleatSt01.7z ... 1st demo Dual Crew BBS Intro stops after a while! (In The Zone!)