try other renderer by holding shift+g down and starting game.
That only cycles through all folders who's name starts with a 'G'. Besides, that has never worked for me, neither starting with shift down nor the option ever showing on the context menu (it just ain't there even with shift pressed)
So, found a copy of Ch7, code also doesn't show anything different, even the images are identical.
Only thing different is the copy I found uses Ren'Py 7.4.11 and my SDK is 7.5.2...
EDIT: Well, it's a Ren'Py bug afterall. Installed the 7.4.11 SDK and the vertical pans show perfectly. But no idea if Sancho's mod will play nice since that obviously was compiled with 8.x