[MaestroDD]

[...]

Can you explain a little about the XBMChelper app? I had a feeling the error was probably mine, but I wasn't able to find any documentation on it in the wiki. I was under the impression that it was just a tool for diagnosing problems.
[...]

sure, I'll try to:
xbmchelper is split into 2 parts:
1) translate raw IR commands from ATV's IR-interface into something like button presses
2) translate button presses to buttons/actions for XBMC (here the optional universal mode comes into play)

On the ATV platform we use 2 different approaches for launching xbmc (details).
When using the "old" Launcher approach (aka Launcher < 1.0) only translation of ATV-Buttons to XBMC buttons is needed: Finder has control over IR interface and nicely sends buttons to Launcher. So we use only part "2)" of xbmchelper and that part is directly built into Launcher < 1.0 (no external xbmchelper application)
With the MultiFinder approach (aka. Launcher >= 2.0) there is no Finder running and that's why we start the external xbmchelper to do IR-handling ("1)" and "2)" from above)

Problem is that part "2)" has bugs you discovered (no combinations with buttons +,-,...). With the MultiFinder approach you can now easily exchange the xbmchelper application with the fixed one. For Launcher 0.x approach a whole new Launcher is needed (which will probably arrive in the next days as Launcher 3.0 -> combination of Launcher 0.x and 2.x series).

HTH,
stephan