Same old story
2 errors unescaped ampersands
9 errors on calendar.

• 1 and 2 Un-escaped &s Suspect as in version 5:

  [/inc/widgets/widgets/_user_login_widget.php] &redirect at Line 226
  
  [inc/users/model/_user.func.php] Lines (198,212,214,2x225,270,736,1766,1835,2x3162,3849,2x 3851,3853,3857,3869,3884,3899,4372,4379)

  Only did the green numbers as this fixed it for now. Think it's just line 225
  
  

• 3. Cellspacing not valid attribute
  4. summary not valid attribute
  6 to 11. 'attr' not valid attribute

  Line 437 removed cellspacing="0" and replaced the word summary with title
  line 452 removed abbr="[abbr]"