Did your manifest always look like that, with no "icon" entries? I just tried a test with a manifest with no icon entries and sure enough I got the insufficient storage message when I tried to go to the channel from the Channel Store. Add the following entries and see if it helps:
mm_icon_focus_hd=pkg:/images/iconHD.gif
mm_icon_focus_sd=pkg:/images/iconHD.gif
mm_icon_side_hd=pkg:/images/iconHD.gif
mm_icon_side_sd=pkg:/images/iconHD.gif
I don't think the icons even have to be in the package (you'll just get a blank square on the main menu), but you might want to create them anyway.
-JT
Roku Community Streaming Expert
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