To use the annotation with the multi-page environment, an active page must be selected with the AnnoSelectPage method call. Some of the methods will operate only if the selected object is on the selected page. For details, please see the AnnoSelectPage method. See the source below:
Private Sub Load()
…
Doc(iTag).BiDisp.hDib = hDib
Doc(iTag).Anno.AnnoSetDPI hDib
Doc(iTag).Show
Doc(iTag).SetExtent
Doc(iTag).Anno.AnnoSelectPage (nImage)
Doc(iTag).Anno.AnnoUIEnableUI (True)
Doc(iTag).Anno.AnnoUIEnableDrawFrames (True)
Doc(iTag).Anno.AnnoUISetChange (False)
Doc(iTag).Anno.AnnoUISetRecalc (True)
Doc(iTag).BiDisp.UpdateControl 0, 0, 0, 0
…
End Sub