Static route between two OpenWrt networks

Thanks,
I have made changes that at this point I am able ONLY to ping from 10.7.7.1 to device on Lan8 and from 10.8.8.1 to Lan7 Only.
I am able ONLY from the routers and not the devices on from 8 to 7 and from 7 to 8.
I have been changing a lot and I would be happy if anyone can focuse me again on what I should need to have in my settings in order to make sure that I am not losing what I have now and also to be able to get the full connections from Lan8 and Lan7 both ways.

Thanks.