Line 704, Column 20: end tag for "SCRIPT" omitted, but its declaration does not permit this
          doc.write('</form>');
✉
You forgot to close a tag, or
you used something inside this tag that was not allowed, and the validator is complaining that the tag should be closed before such content can be allowed.
The next message, "start tag was here" points to the particular instance of the tag in question); the positional indicator points to where the validator expected you to close the tag.

          doc.write('<input name="pcv_strCurrentUrl" type="hidden" value="' + pcv_jspCurrentUrl + '" \/>');          
          doc.write('<\/td><\/tr><tr><td align="center">' + "Loading Product Images... If the images do not appear in 15 seconds <input type='submit' name='Submit2' value='Click Here' id='submit2' class='submit2'>." + '<\/td><\/tr><\/table>');
          doc.write('</form>');
          doc.write('</div>');