"Liveview looks like this:" -> that's a bug; ML shouldn't print things over Canon's overlays. To solve it, one has to find a property that tells us when these overlays are turned on or off; however, I have a feeling it's just a simple tweak. Try this patch:
--- a/src/propvalues.c
+++ b/src/propvalues.c
@@ -239,3 +239,3 @@
hdmi_vars_update();
- #elif defined(CONFIG_60D) || defined(CONFIG_600D) || defined(CONFIG_1100D) || defined(CONFIG_50D) || defined(CONFIG_DIGIC_V)
+ #elif defined(EVF_STATE) || defined(CONFIG_50D)
lv_disp_mode = (uint8_t)buf[1];
That makes the code path with buf[1] available to all models using EVF_STATE (recent DIGIC 4, all DIGIC 5 and also newer models); these are likely similar, but it's something I'm unable to test in QEMU for now.
To test: press INFO/DISP a few times. ML overlays should appear only when Canon overlays are turned off (not both at the same time, fighting over the screen).
Raw video preview: mlv_play does not use display filters (previously, it should have worked in the same way). There's an option in the submenu to change the preview mode - you'll notice it right away, as it has low frame rate and looks ugly. Or, try the fisheye correction, which is the most demanding preview option (memory hungry).
FPS timers are in the submenu (timer A and B). Just write down their values. To change video modes, use Canon menu (1920x1080 24/25/30 fps, 1280x720 50/60 fps, x5 zoom etc).
Some related stuff that wasn't done for 1200D:
VRAM dumps in all video modes.