ok got it! i'm using Cross on a laptop and also on a netbook.
on the netbook the panel for autolooping is hidden from the explorer,playlist,iTunes bar.that bar has an minimum height so i can't see autoloop bar in full screen mode.
Maybe for improve flexibility on small screens it may be useful to give the possibility to the user to hide the track selection bar(or at least leave the minimum height).
thanks anyway guys !
(for now i switch off full screen mode to select effect...so annoying..

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