http://imgur.com/CpNVD3k

This is known, but very strange

I think I found the issue,

in prototypes/buildings/omnitracker.lua file
change line 67

sound = { filename = "angelsrefining/sound/ore-crusher.ogg", volume = 0.8 },

to the following,

sound = { filename = "omnimatter/sound/ore-crusher.ogg", volume = 0.8 },

I did that on my local copy of the mod and it fixed the error.

One reason why this might not show up is if you have angels refining installed it will find the sound file and load properly. But if you delete that mod from your mods folder then factorio can't find the file and it will give the error shown. But if you change the sound reference then it removes the problem all together.

The only Angels items I have are Warehouse and Pressure Tanks. I am running Bob's mods, though.
Mostly, I wanted to try this mod out to see what it really did, since I don't understand yet how it would improve things to have just one type of resource. Basically giving it a go.

I have solved it now in the current version :)