[OZ4]

apERNA1885  looking at your pictures. The white diagonal twitchy lines are the horizontal retrace which is normally blanked out but the brightness is up so high that they are showing. This is normal with the brightness all the way up.

Also it looks like the horizontal osc is locking as I can see the grid pattern. Will the picture tear when you adjust the horizontal control?  If it will tear then the oscillator is locking.

Your rolling distortion is likely horizontal Bars banding the screen that can be the line AC interference getting into the video signal coming thru the IF amp. Or maybe getting into the vertical deflection. 

As I understand it BW sets vertical ran at 30hz That's one full screen every 1/30th of a second. Then when the color system came online it chanced to 29.97hz as to not interfere with the color signals. (N.T.S.C.  Never The Same Color twice) And the older BW sets could still lock on to the new 29.97hz vertical sync signal. So when all other things are working this difference is why there can be  moving bars of interference from the AC line. Two bars is 60hz and after the rectifier section 120hz can be four bars.

(Many years ago I was a TV broadcast engineer but didn't work on tv monitors much. I was mostly tasked with keeping the beta tape machines up and running.)

The really fine horizontal lines maybe ringing (high frequency oscillation) in the IF section or the vertical section. 

And there is still distortion in the vertical deflection waveform. Hence the lack of full picture with fold over.