Dotty Crown Seeking Palindrome

Normal 6x6 sudoku rules apply: each column, row, and 2x3 box must contain all the digits from 1 to 6. Digits seperated by a king's move (in chess) cannot contain the same digit. Digits separated by a white dot are consecutive. Digits seperated by a black dot are a 1:2 ratio. Not all dots are given. Clues outside the grid give the sum of the digits between 1 and 6. Digits on a grey line are a palindrome and read the same forwards as backwards.