Interesting. What do you mean by the Startup Screen? The RESTORE key should only be active in the game itself. You can't hit RESTORE on the title screen for example, it won't do anything. I've hit RESTORE at various points in the game when the level starts up and it quits back to the titles as normal. I've not managed to recreate the issue on my version of VICE 3.4 and on my Ultimate64e. I will have a look into it further though.
It would be interesting to see your C64 MAXI video at some point. I know that Kawari does have some issues over a normal VIC-II chip. There are some bugs still floating around, I've seen some posts on forums regarding this. Some games don't work at all properly.
Thanks for your feedback.