RTB Mod Manager initilization error(not a problem though?)

[GEN.Fire Bird]

could someone please explain what this means?
i captured this during V20, but its still a re-occuring thing

[Ad Bot]

[Peejster]

It means that, for some reason, System_ReturnToBlockland is counted as a crap-on, and can't be used in the game.

[GEN.Fire Bird]

Yet it loads and runs fine.

[Ephialtes]

It's nothing to worry about. It's just the way the mod manager loads all of your installed add-ons.

[Pacnet2012²]

Yes, it's just checking if any of your add-ons are in the CRC (Crap-Cache) or aren't packaged properly and obviously one of your add-ons is, so it prints that error.

[GEN.Fire Bird]

it displays those errors 6 times per load.
also this:
Add-Ons/System_ReturnToBlockland/interface/mods/addOns.cs (25): Unable to find object: 'AddOnsGui' attempting to call function 'delete'
BackTrace: ->onStart->serverPart2->initClient->loadClientAddOns->interfaceFunction