In response to your original question: The only error I've been having with Prat has to do with the fact that addons can't modify friendly nameplates in instanced content. Disabling the bubbles module resolves that issue. A fix would require that module check if the player is in an instance, and not modify nameplates/chat bubbles while they are. The call stack is the same as Lovykar's on the first page.
I too was looking for a place to report issues/submit patches, and with the old forums going down, disabled comments on the mods.curse.com, this is the only place I've found.
If you're using the OriginalButtons module and don't want to have errors with the previously named 'Social' button, patch OriginalButtons.lua replacing FriendsMicroButton with QuickJoinToastButton in two locations:
--- ./World of Warcraft/interface/addons/Prat-3.0/modules/OriginalButtons.lua Mon May 16 22:24:09 2016
+++ ./World of Warcraft/interface/addons/Prat-3.0/modules/OriginalButtons.lua Sun Oct 30 12:51:21 2016
@@ -505 +505 @@ function module:OnModuleEnable()
@@ -557 +557 @@ function module:ConfigureAllFrames()