in radioactivity_field_widget_form()

I'm receving this notices in almost every page (not only in node/*):
Notice: Undefined index: radioactivity_timestamp in radioactivity_field_widget_form() (line 230 of [...]/sites/all/modules/radioactivity/radioactivity.field.inc).
Notice: Trying to get property of non-object in radioactivity_field_widget_form() (line 253 of [...]/sites/all/modules/radioactivity/radioactivity.field.inc).

Or this (in admin/structure/types/manage/blog/fields):
Notice: Undefined offset: 0 in radioactivity_field_widget_form() (line 230 of [...]/sites/all/modules/radioactivity/radioactivity.field.inc).
Notice: Trying to get property of non-object in radioactivity_field_widget_form() (line 253 of [...] sites/all/modules/radioactivity/radioactivity.field.inc).
Notice: Undefined offset: 0 in radioactivity_field_widget_form() (line 258 of [...] sites/all/modules/radioactivity/radioactivity.field.inc).

I have installed the 7.x module, and added a new radioactivity field for the blog type content.