[Phanx]

Keep in mind that files are loaded in the order they are listed. Your list of libraries will result in a lot of errors on login, because you're loading libraries that depend on other libraries before the libraries they depend on. For example:

* AceDB-3.0 depends on CallbackHandler-1.0, but you're loading AceDB first.
* Part of AceConfig-3.0 depends on AceGUI-3.0, and another part depends on AceConsole-3.0, but you're loading AceConfig before either of those.

Also, AceGUI-3.0-SharedMediaWidgets requires both AceGUI-3.0 and LibSharedMedia-3.0, the latter of which isn't mentioned anywhere in the XML you posted, so I have to assume you're not loading it at all.

If you don't see any errors, make sure that:

1. You're testing without other addons enabled. If your addon is still called MayronUI, but you're also using Archy, for example, then the libraries in Archy will already be loaded when your addon loads, hiding the problem.

2. You have BugSack installed. The default error display, even if you've turned it on, is incapable of showing errors that occur during the initial loading process, and is therefore useless for addon development.

Unrelatedly, I would suggest loading the library's Lua file directly if you know it only has one file, rather than loading an XML file that loads the Lua file. Reading files from disk is by far the slowest part of the loading process, so the fewer files that need to be read, the better.

Assuming the file paths themselves are correct, I'd suggest this:

<Ui xsi:schemaLocation="http://www.blizzard.com/wow/ui/
..\FrameXML\UI.xsd">
    <Script  file="libs\LibStub\LibStub.lua"/>
    <Script  file="libs\CallbackHandler-1.0\CallbackHandler-1.0.lua"/>
    <Script  file="libs\AceAddon-3.0\AceAddon-3.0.lua"/>
    <Script  file="libs\AceConsole-3.0\AceConsole-3.0.lua"/>
    <Include file="libs\AceGUI-3.0\AceGUI-3.0.xml"/>
    <Include file="libs\AceConfig-3.0\AceConfig-3.0.xml"/> <!-- depends on AceConsole, AceGUI -->
    <Script  file="libs\AceDB-3.0\AceDB-3.0.lua"/> <!-- depends on CallbackHandler -->
    <Script  file="libs\AceDBOptions-3.0\AceDBOptions-3.0.lua"/> <!-- depends on AceDB -->
    <Script  file="libs\AceHook-3.0\AceHook-3.0.lua"/>
    <Script  file="libs\AceLocale-3.0\AceLocale-3.0.lua"/>
    <Script  file="libs\LibAboutPanel.lua" />
    <Script  file="libs\LibDataBroker-1.1\LibDataBroker-1.1.lua"/> <!-- depends on CallbackHandler -->
    <Script  file="libs\LibDualSpec-1.0\LibDualSpec-1.0.lua"/> <!-- depends on AceDB, AceDBOptions -->
    <Script  file="libs\LibSharedMedia-3.0\LibSharedMedia-3.0.lua"/> <!-- CallbackHandler -->
    <Include file="libs\AceGUI-3.0-SharedMediaWidgets\widget.xml"/> <!-- depends on AceGUI, LibSharedMedia -->
</Ui>