Very happy to see and load up beta V2. Here is my initial feedback.
CHDK OSD
1 - The CHDK OSD now displays in RECORD and PLAYBACK. It occasionally and seemingly randomly fails - mostly the camera freezes - lens still out - pressing DISPLAY brings it back to life along with CHDK menu retained. On a couple of occasions it has crashed and needs to be rebooted. Is their a debug file I can set that would help to isolate what was happening at the time? Other values set to display are shown and look correct though I have to go over in a bit more detail e.g. Tv as set in CHDK is correct, battery, files.
2 - With the CHDK OSD displayed in RECORD mode the normal camera controls work e.g. in Av can set aperture, EV, mode (macro etc), flash and switch between the Canon menu's.
CHDK Menu
3 - Not as stable as beta v1 - ocassionaly disappears when navigating though menu items. If that happens by pressing the up \ down buttons for example the CHDK menu comes back - sometimes part of it, sometimes in stages and other times all of it in one go.
4 - Jogwheel does always seem to work when navigating all menu items. I will test this again later and try to provide some specific examples when I can repeat.
Overrides

5 - Tv. Appears that on a single shot the camera is not exposing as set in CHDK. If the shutter is half-depressed it first does show the Tv value set but then changes to what the Canon system calculates. On taking the picture the exposure value shown is as set in CHDK but the image appears to have been exposed by the Canon calculation. I did a couple of shots where the Tv value should have produced for example an under exposure. I made sure safety shift was off on the Canon menu.
6 - Bracketing. This is nearly working as I expected

For me this is great - OSD \ Histogram are move to have but secondary - having this functionality gives us control of the exposure. Even though single Tv exposures do not seem to be taken as per the CHDK value set when in bracketing mode with continuous exposure it is working. It looks like that in each of my first shots in the sequence though is as in 1) above it is not made according to the Tv override value set in CHDK - however the rest of the sequence is correct ! I will look at this in a bit more depth later and run some better test sequences and play around with other Tv functions in CHDK and see how they perform.
Histogram and other OSD items
7 - The display area comes up on the OSD but I am not getting a live histogram - its a single color box. I have tried various color settings in the Menu items for the histogram background, border, lines etc but nothing actually gives me a viewable live histogram. Nothing on zebra or outline either but I didn't expect to see those.
RAW
8 - While set up in CHDK I am unable to save a RAW image file - also the OSD says "RAW DISABLED" on stat values on the CHDK OSD even though as I said the CHDK Menu is set up to save RAW images. Strange.
Conclusion to date
V2 is a big improvement - OSD values shown and Tv \ bracketing. If you could get Av \ aperture overrides to work in the same way, and I assume aperture bracketing as per Tv above would also work, this would at least give a high degree of control and would be a great start. Will do some more extensive tests later and update this post.
Thanks again !!