I see no way to add the 1d4 through new sheet. On 2014 sheet there were such options, set for the character affected. You could create a macro called Guidance Guidance add [[1d4]] Then make it a Token Action and visible to all players. Players then can click this when needed. You could create more complex macros, but until the sheet is stable/complete I don't think there is much point. So much does not work, and so much is just missing there's a lot of work for Roll20 to do and much will no doubt change.
