Please disregard my email I sent earlier today. Here is the path that works for me to get the two characters I originally mentioned and also an additional one (this is on Debian Sid, so the path a bit different):
# diff gur gur-hs
50c50
< key <AC07> { [], [ 0x1000A30, 0x1000A30 ] };
---
> key <AC07> { [], [ 0x1000A30, 0x1000A5C ] };
57c57
< key <AB01> { [], [ z, Z ] };
---
> key <AB01> { [], [ 0x1000A71, 0x1000A01 ] };
In the above, gur-hs is a copy that I modified and gur is the original layout. For the addak case, I have now moved it to the Z key on a US keyboard. That key was unused and I didn't see a point of not using it and using third level chooser to that character. The way I have shown above works better.
There are a few other characters that should be included. Do you think I should send patches for them too?
BTW, my earlier comment that I am not sure if there a "standard" which specifies where each character should go on a gur layout still stands.
thanks and best regards,
->HS